Spatial heterogeneity and trans-boundary pollution in cross drainage basin: a contingent valuation study on Xijiang River drainage basin in South China? Jie He1, Anping Huang2, Luodan Xu2 This version May 6th 2014 (Preliminary version, please do not cite) Abstract This article aims to examine whether and how the location of a city along a river can affect its residents’ Willingness to Pay (WTP) for a river water quality improvement project. The underlying mechanism is the transboundary river water pollution spillover which may reduce people’s expectation about the utility increase that they can obtain from cleaner water, therefore leads to under-reported WTP. Our analysis is based on a CVM survey conducted in 20 cities of 4 Provinces of South China located in the Xijiang river basin during July-August 2012. To test this hypothesis, the water quality of the part of Xijiang River belonging to an upstream city is included into the determination function of the WTP of a respondent living in its direct downstream city. Our results demonstrate that besides the city-specific river water quality and other macroeconomics characteristics, the upstream city’s water quality is also a significant and negative determinant in the formation of WTP. A downstream city’s respondents report lower WTP when their direct upstream is more heavily polluted. We also found the negative externality on WTP of downstream cities to be decreasing with the distance that separates them from their direct upstream city. This negative externality is also proven to be mitigated by the negotiation power of a downstream city with respect to its direct upstream counter-partner. Our results reveal that higher is the negotiation power of the downstream city (measured by relative ratio of per capita gross regional product (GRP), GRP growth rate and population size), lower will be the impact of negative externality of transboundary pollution on WTP. The under-reported WTP due to the transboudary river pollution reminds us of the potential huge social benefit that can be created by a river basin level water quality management project, which, if functioning efficiently, can largely reduce the concerns of the downstream people about the pollution spillover from the upstream cities. Our study also provides interesting insight about the huge potential of the hotly debated pilot payment for ecological service regime between upstream and downstream regions, considered as a market-based solution for transboundary river water pollution control in China. Keywords: transboundary water pollution, river, negative externality, spatial, contingent valuation, China 1 2 University of Sherbrooke, Quebec, Canada. Jie.He@usherbrooke.ca. University of Sun Yat-sen, China. 1. Introduction The stated preference non-market valuation methods are very often used to assess public preference for environmental quality improvement policies or projects. Although the spatial characteristics may play an important role in willingness-to-pay (WTP) determination (e.g. Bockstael, 1996; Johnston et al. 2002, Bateman et al. 2006, etc.), the increasing attention to include consideration of the spatial characteristics in stated preference studies are relatively recent, the earliest ones can be traced to Desvousges et al. (1987) and Bockstael (1996). Johnston et al. (2002) suggested that “[the] omissions [of spatial factors] may be particularly troubling in case where the survey instrument itself provides cartographic details that respondents may associate with particular spatial characteristics”. Many conventional WTP determinants, varying from initial environmental condition to some specific economic characteristics (Bateman, 2009), may present large spatial heterogeneities, are therefore able to diverge the value of WTP of people living in different places for a same environmental quality improvement project. The spatial preference heterogeneity can be potentially important for the river water quality related valuation studies. As large scale generic resources, rivers often flow through boundaries between political jurisdictions (communities, cities, provinces and even nations). If the different sides of the boundaries apply diverged environmental policies, combined with initial difference in geographical and economic conditions, water quality across boundaries may not be uniformly and continuously distributed but more patchy and discrete in their presence (Jørgensen et al., 2012). Previous studies such as Tait et al. (2012), Moore et al. (2012) and Lanz and Provins (2013) have already provided some solid evidences about how the WTP of a respondent to be dependent on the very spatially precise initial environmental quality or other related characters, under the terms of “spatial scope sensitivity”. In this paper, besides the “spatial scope sensitivity”, we will study another dimension of factors that may also affect people’s WTP in a spatial way, this is the transboundary pollution, a phenomenon closely related to the public good characteristic of river water. The flow of rivers creates up- and downstream regions. The administrative boundaries between regions, however, do not prevent pollution acrossing regional borders. Without a uniform water quality standard applied to the whole river system, which respects the basic Samuelson condition and equalises the marginal benefit from water quality control summed over all regions along the river to the marginal abatement cost, a polluting upstream region, either not experiencing the full benefits of pollution control or not bearing the full cost of pollution damage, may not exert sufficient control of their pollution discharge into the river. Even worse, Oates (2001) further indicates such a situation can lead to a race to the bottom of the regional water quality control policies. In such situation, given a same hypothetical water pollution improvement scenario, further a person living in the downstream part of the river, stronger could be his/her doubt about the possibility of enjoying the proposed better water quality, therefore lower would be his/her WTP, everything else being equal. Not yet investigated by the valuation literatures, the existence of the phenomenon of riverlevel transboundary pollution has already been confirmed on international and province/state level in the studies directly focusing on the spatial distribution patterns of river water pollution concentration. Sigman (2002) used the biochemical oxygen demand (BOD) data measured by 291 river monitoring stations in 49 countries during 1979-1990 from GEMS/Water 1 and found that the BOD indicator to be significantly higher at stations upstream of borders than other comparable stations, at least for the stations located in non EU (European Union) countries. As most US federal environmental policies give the responsibility of regulation implementation and enforcement to state level, Sigman (2005) also investigated the potential trans-boundary spillover phenomena inside of the US, using a composite water pollution index based on five major pollutants compiled from the data of 618 monitoring stations on rivers in the US from 1973-1995. Based on a difference-indifference logic, Sigman (2005) revealed that, all else equal, a water quality index to be significantly 4% worse at the stations downstream from a state authorized with the discretion to implement and enforce environmental regulation. Using GIS water quality panel data of 321 monitoring stations across Brazil and the data about the modification of jurisdictional boundaries of 5500 Brazilian counties, Lipscomb and Mobarak (2007) studied whether water quality across jurisdictional boundaries deteriorates due to the increase in pollution close a river’s exist point out of a jurisdiction. Their results also confirmed a pollution increase of 2.3% for every kilometer closer a river get to the exiting border is within 5 kilometers. The transboundary pollution phenomena are not only limited to river water pollution, but also in air pollution aspect. Gray and Shadbegian (2004) examined the determinants of environmental regulatory activities on air and water pollution of 409 US pulp and paper mills during 1985-1997 and found both the inspection and monitoring efforts reduce significantly for plants located close to a state border, since the out-of-state residents receive a larger share of benefit of these pollution control activities. Helland and Whitford (2003) also report a transboundary spillover case for air pollution in US, illustrated by higher toxic chemical releases in border counties. The principal hypotheses in this paper will therefore be that the geographical location of a respondent along a river basin can significantly affect his/her demand for river water quality improvement, not only through the current river water pollution situation and other related social and economic condition of the regions where reside the respondents, but also through the geographical location of the regions along the river relative to other regions. To test these hypotheses, this paper reports a study using Contingent Valuation method (CVM) to examine the determinant factors for people’s willingness to pay (WTP) for a hypothetical river water quality improvement project. Our CVM survey was conducted in 20 cities of 4 Provinces of South China belonging to Xijiang river basin during July-August 2012. Xijiang Rivier is an interesting case for spatial-related study since the regions along this river present high disparity in economics development and environmental pollution during the last several decades. Dichotomous choice and MBDC format WTP questions were randomly presented to local residents of the 20 cities. City-level macroeconomics and river water quality data are used in econometrics model along with individual-level socio-economic characteristics to measure the heterogeneity of WTP between people living in different cities for the proposed water quality improvement. Moreover, our paper will pay special attention to test whether and how the water quality and polluting economic activities of the upstream cities have significant impacts on the preference and perception of the downstream cities for a same river quality conservation project. One of our central finding is that, although in general, respondents living in the cities facing more polluted river water are willing to pay more, all else being equal, those living in downstream of Xijiang river report significantly lower WTP when their upstream is heavily polluted. We also test the robustness of our results by adjusting the influence of water quality of the upstream city with the distance from the direct downstream city to it and with 1 UN’s Global Environmental Monitoring System Water Quality Monitoring Project. the relative negotiation power of direct downstream city with respect to it, and obtain quite stable results. These findings actually reveal the necessity to include the inter-relationship between regions located on a same river in CVM study while studying a river basin level water quality improvement project, in the aims to take care of the negative externality of river water pollution. The paper is organized as follows: in Section 2, we reviewed spatial factor related stated preference valuation literature. Section 3 outlined the river basin level transboundary pollution situation in China. Section 4 presented the background of Xijing river basin. Section 5 and 6 provided some details about our survey and about data cleaning works. Section 7 discusses the principal hypotheses to test under the scenario of river transboundary pollution. The main models, results of our estimations and the robustness check will be given in the section 8 and 9. Finally, we will provide some discussion in section 10 about the pertinence and policy implication of our findings for China’s pilot ecosystem service compensation mechanism which aim to reinforce transboundary coordination in river pollution control. Finally, we will conclude in Section 11. 2. Literature Review Spatial factors get increasing attention in recent stated preference (SP) environmental valuation studies. 1 Such research interest is mainly motivated by the potential spatial preference heterogeneity. Considering the spatial preference heterogeneity can affect both the size of the economic jurisdiction in which relevant people have positive WTP (Bateman et al. 2006; Hanley et al. 2003) and the sample mean WTP (Bateman et al. 2006; Pate and Loomis, 1997; Bockstael, 1996): the two factors on which the aggregation of total benefit for non-market goods commonly relies; more and more authors believe without controlling spatial heterogeneity can come at the cost of the precision of aggregate WTP. A good example is Bateman et al. (2006), in which the authors found the aggregate WTP based on the “economic jurisdiction” and spatially controlled individual WTP comes out to be sixteen times smaller than the simple aggregate WTP based on “geographical jurisdiction” and sample mean individual WTP. The most frequently discussed spatial heterogeneity in the literature is the so-called “distance-decay” (Loomis, 2000), which suggests WTP to decline with the increase of the distance between a respondent’s place of residence and the site providing ecosystem services. (Schaafsma et al. 2013). Various reasons have been proposed in the past decade to explain/interpret distance-decay. Sutherland and Walsh (1985) believe the information about the valuated site motivates positively people’s WTP, a longer distance can lead to higher cost to obtain the information about the site, and therefore reduces people’s WTP. Hanley et al. (2003) pointed out the necessity to differentiate between user and non-user, and found more rapid distance decay exists for use value than for non-use values. Bateman et al. (2006) underlined the potential difference in the nature of distance decay between the equivalent loss studies which examine preservation value and the compensation surplus studies which estimate the environmental improvement value. As it is more possible to have non-users to convert to user in environmental improvement project and the conversion from non-user to user is more likely to occur for households nearer to the resource, Bateman et al. (2006) therefore suggested that the distance decay can be observed among either user or non-user, 1 Past literatures already studied numerous spatial attributes and their impact on people’s preference for ecological goods and services provided by large-scale ecosystems as river (Desvousges et al. 1987; Holmes et al. 2004; Zhiqiang et al. 2002), forest, wetland and other eco-system (Broch et al.,2012; Guimarães et al.,2011; Zhongmin et al.,2003), etc. at least for the compensation surplus studies. Other authors tried to explain the distance decay by the availability of substitutes (Brouwer and Slangen, 1998; Hanley et al. 2003; Jorgensen et al., 2013 and Schaafsma et al. 2013). As the number of substitutes often increases with the distance from the valued site, greater is the distance, lower will be the demand for the valued site, and therefore lower will be WTP. Schaafsma et al. (2012) tried to further refine this logic by identifying the directional heterogeneity in the availability of the substitutes, which may affect the distance decay phenomenon in a heterogeneous way in different directions. Finally, Some authors (Sutherland and Walsh, 1985; Rolfe and Windle, 2010, Jorgensen et al. 2013, among others) also mentioned the importance to distinguish between generic non-market resources (i.e. the wetland in a country) and an iconic ones (i.e. Yellow Stone national park or the Great Barrier Reef), distance decay affects less likely these goods with large scale importance, as people’s awareness and knowledge about them are less sensitive to the distance and there are few significant substitutes. Parallel to the phenomena of distance-decay, spatial scope sensitivity (Lanz and Provins, 2013) is another aspect of spatial preference heterogeneity that starts to attract researchers’ interests in SP studies. More pertinent for generic natural resource with relatively large geographical scale and non-homogeneously distributed quality/quantity, spatial scope sensitivity interests in understanding how an individual’s WTP varies according to the spatial variability in the quality/quantity of an environmental resource itself. Johnston et al. (2002) examined how the WTP for rural land development project is dependent on whether or not the developments located adjacent to main roads, etc., Moore et al. (2012) found respondents’ WTP for a universal water clarity improvement in Green Bay, Wisconsin to be dependent on the initial clarity of the water closest to their residence. Since the dirtiest part of water in the bay is close to population center, they found their “geospatial referencing model” give much higher aggregate willingness to pay for the project then the base mode which suggests households to be a single entity defined only by its average water quality in the bay. Tait et al. (2012) combined the spatially related water quality data into their choice experiment study via the Geographical Information System (GIS). They found that the respondents who live in the vicinity of low quality waterways are generally willing to pay more for the improvements relative to those who live near to high quality waterways. Broch et al. (2013) studied how farmers’ willingness to provide a good or services are affected by spatially heterogeneous in species richness, human population density, share of are with special groundwater interests, share of the forest cover and hunting resources, their conclusion also confirms the necessity to include spatial variations in designing conservation policies. The studies interested in spatial scope sensitivity therefore focalize more on the characteristics of the valued goods and services themselves and the geographical variability of these characteristics. These mark their differences from the studies of distance-decay, which give more attention to the distances separate the individuals from the valued goods/services and availability of their substitutes. Naturally, the spatial scope sensitivity related studies depend more heavily on the availability of the geographical data describing the spatial differences in either quality or quantity of the valued goods and service. It is also these geographical data that enable the studies to provide precise WTP estimation in more detailed geographical scale. Another dimension of factors that can provoke spatial preference heterogeneity, to which we can group the preference heterogeneity caused by river drainage basin trans-boundary pollution problem that we will study in this paper, is the potential inter-relationship between people of different regions. An improvement project applied on a generic natural resource can be viewed in different ways by respondents living in different place according to how the provision of the natural resource can be spatially differentiated and how this spatial differentiation can affect the utility improvement for a respondent located in a specific location. Brouwer et al. (2010) provided such an example. By assessing the preference heterogeneity related to the spatial distribution of water quality improvement throughout a river basin via a choice experiment study, they found that irrespective of the sub-basin where people live, the improvement of water quality to a good state is valued equally by local and non-local residents. However when improving water quality on level further to very good quality, local residents place an additional value on this improvement if it occurs in their own sub-basin. Another interesting example is Lanz and Provins (2013), which examined explicitly how the preference of respondent changes with the location of improvement project by including the coverage of policy as an attribute in their choice experiment design. Besides finding logical strong preferences for improvement in local environmental amenity, they also observed that with the enlargement of the spatial coverage of the project, preference heterogeneity between regions increases, accompanied by a declining in the sample mean WTP. Their explanation is that “for some attributes, respondents can display negative surplus for the provision of improvement in other nearby regions, which signals competition for the appropriation of rivalrous benefits” (Lanz and Provins, 2003, P107). Our paper enters naturally to the spatial scope sensitivity literatures since people’s WTP is assumed to be directly related to their location along the river, but the particularity or the innovative point of this study compared to the existing spatial related studies is that we will put more attention to the inter-relationship between cities/regions along the same river and how this inter-relationship can affect directly people’s WTP. This is according to our knowledge the first paper discussing this aspect of spatial preference heterogeneity, Moreover, our study also brings an interesting case for the empirical river basin transboundary pollution literatures as Sigman (2002, 2005) etc., although the transboundary phenomenon is analyzed in our paper indirectly. Our study also differentiates from the other existing non-market valuation studies aiming at valuing the water related ecological services in China and other developing countries and regions, such as Wei et al.(2006) in the North China Plain, W. Yang et al.(2008) in Hangzhou, China; Tong et al.(2007) in Wenzhou, China, Zhiqiang et al.(2002) in Heihe river basin in China, Zhongmin et al.(2003) in Eijna region of China, Choe et al.(1996) in Philippines, Vásquez et al.(2009) in Mexico, Boadu(1992) in Ghana, Hammitt et al.(2001) in Taiwan., etc. Those previous studies were more focused on specific regions/areas, instead of taking the whole river basin into consideration, even less have they discussed the potential role played by spatial factors in value/preference determination. 3. River basin level transboundary pollution in China Most of China’s large-scale river basins are composed of several regional jurisdictions (province/region/city). It is therefore evident that decisions taken by one regional jurisdictions can have implications across administrative boundaries, just as what have been reported for the international case or those from the US and Brazil. From the point of the view of environmental regulation, this risk seems to be confirmed for China, because although in general environmental policy is formulated centrally and local jurisdictions have only the authority to set their own environmental standard more stringent than that of national level, the implementation responsibilities are devolved to the branch office of Ministry of Environment Protection (MEP), operating at the provincial, municipal and county levels (Hills and Robert, 2000). The monitoring and enforcement efficiencies of these branch offices of MEP are largely affected by the complexity and fragmentation of the different authorities. Yu (2011) describes the complex relationship between the Ministry of Water Resource Management (MWRM) which deals with water quantity and water utilization and the MEP which coordinates and solves trans-boundary environmental pollution disputes. He believes there are either overlaps or gaps between the competences of the two authorities, which may largely compromise the efficiency of their efforts in trans-boundary river water pollution control. Hills and Man (1998) indicated that the policy enforcement difficulties in China can be further compound by the networking relationship (guanxi in Chinese) between regulators and polluters, which can result in erratic and inconsistent enforcement of environmental protection measures. Yu (2011) believe such a possibility is especially true in the current context where the budget of lower branches of MEP is dependent on local governments, who may give higher priority to economic growth instead to environment protection. Another particularity of China is that, given the lack of water resources, it is very common for each jurisdiction to construct water conservation structures, such as dams or floodgates, which may further enable each region to control the distribution of pollutants within its jurisdiction by managing the pollutant flow more directly to the downstream jurisdiction (Zhao et al. 2012) These particularities, along with lack of efficient transboundary pollution agreements and concrete dispute settlement mechanisms, have already caused severe water pollution at trans-boundary interfaces (Wang, 1999; Zhao et al. 2005; Yu, 2012; Zhao et al. 2012). Examples are the blue-green algae out-break in Taihu Lake Basin in May 2007 (Zhao et al. 2012) and the very well documented transboundary pollution between Guangdong Province and Hong Kong via the Pearl River drainage basin (Hills and Roberts, 2001; Hills et al. 1998, Marsden, 2011, among others), etc. 4. Background of Xijiang River Basin Xijiang River is the main stream and longest tributary of Pearl River, the largest river system in southern China. It flows for 2217 kilometers from the north of Yunnan province eastward across 2 southern provinces of China: Guizhou province, Guangxi province and flows through the Pearl River delta in Guangdong province and enters the South China Sea near Macau. Xijiang River basin accounts for 78% of Pearl River basin (409,480 km²) , and it drains the majority of Southern provinces, as well as parts of Southwest of China, According to the 6th nationwide population census of China (conducted in 2010) , the population living inside of Xijiang River basin amounts to 100 million. The regions belonging to the basin are very important in term of economic activities, with an annual gross output of 3790 billion Yuan (2010) and an annual growth rate over 10% until 2012, this river basin covers the most developed area of Southern China. During last 35 years, Xijiang River Basin, like other regions in China, experienced increasing inequality in economics development. Taking the provinces Guangdong and Guangxi as example: before the beginning of economic reform, in 1978, Guangdong’s gross regional output (GRP) per capita was 370 Yuan (220.24 USD), about 1.5 times higher than that of Guangxi (246 Yuan, equal to 146.43 USD). However in 2008, Guangdong’s GRP per capita has reached to 37589 RMB (5408.49 USD), which is about 2.5 times higher than that of Guangxi (14966 RMB, equalt to 2156.48 USD).1 Along with the widen disparity in per 1 The conversion between RMB and USD are conducted with official exchange rate, which was 1 capita GRP, we also observe increasing gap between these two provinces in economics structure, urbanization level, economics openness, etc. Uneven development between regions naturally leads to very different interpretation of regional government about the relationship between environment and economy. Although the environmental conscience start to awake in some richest eastern coastal provinces/cities, many inland western regions are still willing to endorse environmental damage to attract investment in polluting productive sectors. Such a situation may further exacerbates the above mentioned transboudary pollution problem, since a particularity of Xijiang river basin is that most of the poor inland provinces/cities, which are willing to sacrifice environment for growth, are located in the upstream of the Xijiang river basin. Such a situation might unfortunately be further enhanced by the fact that the two inland provinces (Yunnan and Guizhou) located to the upstream of Xijiang River basin are rich in nonferrous metal reserves, whose extraction is very polluting, particularly for water resources, either directly by discharging of mining wastewater or indirectly by extraction-related deforestation and soil-erosion/contamination. The accumulated industrial wastewater pollution further intervenes with huge domestic wastewater discharge burden and great water demand pressure of the alongside cities. All these factors have contributed to the important accumulation of deterioration of Xijiang River water quality, especially for the downstream cities. 5. Survey To measure the WTP for the ecological goods and services provided by the Xijiang River, we conducted in July-Auguest 2012 a large-scale cross-region CVM survey in 20 cities of four provinces (Guangdong, Guangxi, Guizhou and Yunnan) along the Xijiang River. The design of the questionnaire benefited from a series of focus-group composed of researchers, students and experts (both academic and operational) working on hydrology and geography fields. The discussions covered the content and form of questionnaire, appropriateness and efficiency of wording, rationality of the hypothetical scenario, feasibility and credibility of the proposed payment vehicle, etc. Moreover, pre-test was conducted in Guangzhou city with the input of over 50 respondents randomly solicited. Their comments about the questionnaire have been included in final questionnaire. The final version of the questionnaire can be divided into 3 sections: (1) general understanding and attitudes of respondents toward the current condition of environmental and Xijiang River water pollution around sampled city, (2) description of hypothetical scenario proposing water quality improvement and elicitation question of willingness to pay, (3) social-economic and demographical information of respondents and their anticipation of changes in income and welfare if the hypothetical scenario turns to reality. Based on the discussion of focus group and pilot study, tax as a payment vehicle was rejected, since few people shown their empathy to a new tax and doubt about its efficiency in environment improvement. We therefore used voluntary donation as payment vehicle for hypothetical water quality improvement project. To facilitate the understanding of the respondents about the different levels of water quality, we use in the survey the water quality ladder initially proposed by Mitchell et Carson (1989). The river basin level uniform water quality improvement target is fixed at the swimmable level (C level as illustrated in the annex 1), which corresponds to the level II USD=1.68 CNY in 1978 and 1USD=6.95CNY in 2008. in the classification of the Ministry of Environment Protection of China. More recent water quality ladder design, such as the 4D version image proposed in Hime et al. (2009) has also been in our consideration while designing questionnaire, we finally took the simpler but classical version of Mitchell and Carson (1989) due to its simplicity. Moreover, given the current bad water quality of Xijiang, some elements proposed in the water quality ladder of Hime et al. (2009) comes out to be less relevant, since a large part of the ecological service are currently very weak or absent in Xijiang river. Furthermore, few recent experience with cleaner river water environment may also affect respondents’ understanding of certain ecological services proposed in the water quality ladder of Hime et al. (2009). Appendix 1 provides the water quality ladder used in our survey. Two types of elicitation format were employed in split sample in our survey. Randomly, 50% of respondents have encountered a double bounded dichotomous choice (DC2) WTP question and the other 50% have answered their WTP question in a multiple bounded discrete choice (MBDC) matrix. Both questionnaire versions share the same 14 bid price range varying from 0 yuan till 500 yuan. In DC2 version questionnaire, respondents were at first asked “would you like to donate ___ Yuan for a program that will improve water quality of Xijiang river to be clean enough for swimming (level C)?” Depending on his/her answers to this question, a higher/lower bid price will be further proposed. Table 1 present the 14 groups of alternative bids used in the double biding regimes. The MBDC questionnaire invited respondents to fill out the following matrix with their level of certainty to accept each of the 14 bid price, c.f. Table 2. To ensure a uniform and efficient sampling strategy in the 20 cities, we decided to conduct intercept face-to-face survey in public locations. The waiting areas of Outpatient section of hospitals was identified as appropriate places, given their large traffic flow and relative balanced attendance of people of different social classes. 30 students from 4 universities (Sun Yat-sen University of Guangdong Province, Zunyi Medical College of Guizhou Province, Guangxi Normal College of Guangxi Province, Yunnan University of Yunnan Province) were recruited and trained for the survey. Stratified random sampling was used to ensure good balance of representativeness of the 20 surveyed cities. For each city, its sample size was determined as roughly proportional to its total population size. The details of the sample size in the 20 cities are given in Table 3. In total, we got 2223 returned questionnaires. After deleting the respondents under 18 years old and those having lived in sampled city for less than 3 years (to ensure respondent to have enough knowledge about situation of environmental problem in the city), we obtain a total database of 2133 usable questionnaires, in which 1090 were presented with a DC2 version questionnaire and the remaining 1023 were interviewed by MBDC questionnaire. The comparison in respondents’ socio-demographic characteristics between two subsamples in table 4 shows quite good similarity, except the average education years, with the people answered MBDC questionnaire to be 0.7 years longer. Table 5 presents comparison between provinces and with population census data. Clearly, across the 4 provinces, the biggest differences are in average income and education level. Coherent with China’s regional disparity patterns: the respondents from Guangdong province, the richest province in South China, enjoy the highest income and education level. People from Yunnan province, owing to rich natural resources, also report relatively high income but have lowest education level. The respondents from Guizhou and Guangxi in general have much lower income, although the education level is only slightly lower than Guangdong. With respect to census statistics, the gender structure gives good coherence in three over four provinces, except for Yunnan, whose male respondents are over-represented (62.37% vs. 50.85%). Well educated people are overrepresented in all the 4 provinces. This bias can be explained by three reasons. The first is that our survey is only carried out only in urban areas, where the population is in general more educated. Secondly, the survey mode that we chose may discourage less educated people, who may not want to be interviewed by university students. Finally, people may have tendency to over-report their education level since the interviewers are college students. A similar but less important bias of our sampling is age. Table 5 shows that our sample was heavily skewed towards the younger generation, with the majority of people being between 20 and 40 years old. This might also be explained by our survey mode. 6. Data cleaning for WTP answers Details about data cleaning for the answers given to WTP question are illustrated in table 6. Among the 1023 respondents of MBDC question, 119 respondents expressed negative probability to accept the project even at zero bid. We also find 99 respondents affirming their extremely high demand by giving positive responses even at the highest bid price, 1000 Yuan. Another 120 returned questionnaires present missing values in MBDC matrix, which make the answers non-usable. We only find one disordered answers to MBDC matrix WTP question, this shows relatively good understanding of the respondents about the logic of the MBDC questionnaire. For the 1090 respondents of DC questionnaire, 143 respondents gave negative probability to accept the project at zero bid and 37 respondents gave positive answer at the highest bid price. There are also 63 missing answers. The negative answers at the zero bid and the extremely high demand WTP answers can be further classified into different categories based on the answers that respondents gave to the two follow-up questions. As illustrated in Table 7, among the 119 negative zero answers, 102 can be considered as protest (9.74%), with a majority of respondents (87 persons, 8.3%) expressed their doubt about the proper usage of the fund and another 15 persons (1.44%) believe it should be the responsibility of government to support financially the project. The rest 17 respondents expressed their weak demand: little importance of the project (3 persons), the potential heavy financial burden of such a project to their family expenditure (14 persons), we therefore consider their WTP as zero. For the DC2 data, we identified 82 protest answers: 76 expressed their low confidence in the usage of the fund and 6 others believe it should be government’s responsibility. The other 61 persons can be considered as giving real zero WTP. Among the various reasons to explain the extremely high demand responses (c.f. Table 8), we find 73 (=31+42) in MBDC format questionnaire and 35 (=9+26) in DC questionnaire can be considered as unreliable. We can only confirm two respondents in DC survey and 26 (=5+8+13) in MBDC survey as expressing valid high demand for the project. The frequency (in %) of the five probability responses in MBDC for each bid price is summarized in Table 9. The percentage of ‘definitely yes’ answers is decreasing fast from about 92.6% at the price of zero to less than 1.2% at the price of 200 yuan. While the percentage of ‘definitely no’ answers increases steadily with the price offered, from 0% at price of zero to about 95.2% when the price increases to 1000 yuan. Between 20 and 150 yuan, about 50% of the respondents chose the ‘probably yes/no’ or ‘not sure’ response options, showing the respondents actually have relatively important uncertainty in their answers. Table 10 presents the percentage of “yes” responses for each group of alternative bid price proposed in DC2 version WTP question. The percentage number in bold type presents the acceptance rate for the initial bids. The number listed above (below) in the same column reports the acceptance rate for the bid-decreasing (-increasing) path. Vertically comparing, we can observe the logical negative relationship between the acceptance rate and the bid price, especially for the bidding game whose initial bid superior to 20 yuan. Comparing horizontally, we can see that for a same bid price, presented before or after the initial bid can lead to different acceptance rate. This finding is consistent with that reported in Bateman et al. (1999). 7. Hypotheses to be tested Based on the discussion in introduction and literature review, we would like to test the following five hypotheses in this paper. First of all, considering spatial difference in current river water pollution situation, we follow the logic of spatial scope sensitivity similar to Moore et al. (2012) and Tait et al. (2012) and assume WTPi,k of a respondent i of city k to be dependent on the current water pollution situation of the part of river flowing through his/her city, Pk. Logically, higher is the pollution higher should be the WTP, we therefore expect a positive coefficient for this variable. (⏟) for all i living in city k Secondly, due to the transboundary water pollution problem, we also assume that the WTP of a respondent i living in city k to be dependent on the pollution situation of the direct upstream city j. A more severe water pollution situation in the upstream city will discourage respondent’s WTP reporting. We therefore expect a negative correlation between the WTPi,k and the upstream city’s river water, Pj. ( ⏟ ) for all i living in city k, j is the direct upstream city of k Thirdly, we further assume that the transboundary water pollution’s impact on WTP of respondent i living in city k described in H2 to follow the pattern of “distance-decay”. Therefore the negative externality of water pollution situation of the upstream city j on the WTP of individual i in city k decreases with the distance along the river that separates the two cities j and k. To capture this distance-decay effect, we will use a cross-term between Pj and the river distance between j and k Dj,k, where the distance enter as an adjustment term . When city j and k share a frontier which the Xijiang river flows through, the cross term takes the whole impact of Pj, as in H2. When there are some river distance between j and k, the negative externality of Pj on WTPi.k will be mitigated by the distance that separates the two cities. Moore et al. (2012) used a similar term in her measurement of distance decay. We expect a negative coefficient for this cross-term. ( ⏟ ) for all i living in city k, j is the direct upstream city of k We also believe that respondent i’s estimation on the probability to realise the target water quality improvement is also dependent on the negotiation power of the downstream cities j with the upstream city k. Higher is the negotiation power of city j, lower will be the negative externality impact of transboundary pollution on WTP. As suggestion in H4, with an expect negative coefficient, a higher negotiation power of city j will reduce the impact of P j on WTPi,k. We propose to identify three dimensions of comparative indicators to measure the relative negotiation power of city k with respect to j: population size, GDP growth rate and per capita GDP. ( ⏟ ) for all i living in city k, j is the direct upstream city of k Finally, we can also combined the two adjustment effect of the transboundary pollution on WTP together, this gives us the fifth hypothesis: ( ⏟ ) for all i living in city k, j is the direct upstream city of k 8. Estimation Table 11 presents descriptive statistics for the independent variables that we intent to include into the WTP determination function. All individual level variables are directly obtained from the survey. The city-level economic and structural characteristics are compiled by authors based on the data from China Urban Statistics Yearbook for year 2011. The city-level spatial variables are calculated by authors according to geographical information. The water pollution data come from several sources, the details are provided in the Annex 2. The estimation of our WTP determination model is separately conducted for the two split samples. For MBDC data, we use the generalized double-bounded maximum likelihood interval model initially proposed by Welsh and Poe (1998), which, applied to each of the positive certainty levels, can be differentiated into three models: definitely yes, probably yes and not sure; and the two stage Random Valuation Model (RVM) approach proposed by Wang and He (2011) to estimate the WTP determination function. 1 The DC2 data are analyzed by both the simple Probit model which only uses the responses to the first bid, and the double bounded model initially proposed by Hanemann et al.(1991). 1 This method considers the responses given by an individual in the MBDC matrix can be interpreted as the verbal likelihood for him/her to accept the corresponding bid prices, therefore advocate, in a first stage, to use the information to estimate individual WTP distribution, whose mean value signifies the real individual WTP and variance measures the individual uncertainty. The benchmark verbal likelihood coding strategy for our analysis is 1.00 for “Definitely Yes,” 0.75 for “Probably Yes,” 0.50 for “Not Sure,” 0.25 for “Probably No,” and 0.00 for “Definitely No”. The details about the distributions of the estimated individual mean WTP (μ i) and the standard variance (σi) of the entire sample are given in the annex 3. The estimated individual mean WTP is then regressed, in a second stage, directly on the identified WTP determinants, in a linear function form. The results corresponding to Wang and He (2012) presented in the main text are those from the second stage. Tables 12.1-12.3 present the results of estimations for the five hypothesis, using the model of “probably yes” based on Welsh and Poe (1998) approach, the second stage of Wang and He (2011) approach and the double-bound model for DC2 data of Hamemann et al. (1991) approach. The other variants of the Welsh and Poe (1988) and Hanemann (1991) approaches are given in the annex. For each model, the results testing the five hypotheses are presented. As we use three proxies of relative negotiation power (relative population size, ⁄ ⁄ , relative economic growth rate and relative income level 1 ⁄ , the results corresponding to the H4 and H5 are presented each in three columns, each corresponding to one of the three proxy of the relative negotiation power. A general observation from the estimation results of the 3 tables, along with the other three tables in the annex, is the quite similar coefficients for most of the individual-level variables (Environmental perception, socio-economics factors and relationship with the river). As expected, income (income_level) is significantly and positively correlated with the mean WTP in all 6 models. People reporting income to be significantly higher than need are also willing to pay significantly higher WTP. The negative coefficients of the dummy variable (resp_gov) reveals the respondents who believe the environmental protection to be responsibility of government are in general willing to pay less. The level of willingness (will_serve, varying from 5 to 1) to contribute to environmental protection programs is found to be significantly and positively associated with WTP, which signifies respondents with strong will to contribute to environmental protection are willing to pay more. The positive and significant coefficient of the variable quality_deg indicates that respondents who believe the quality of the river water in their cities experienced obvious deterioration have in general a higher WTP. Although not always significant, the positive coefficient of d_fish also confirms that respondents who consume fish at least once a month are willing to pay more for the river water quality improvement project. Logically, people living far from the river seems to report in general lower WTP (c.f. the negative coefficient before far from the river). The three city-level macro-economic variables in general report quite significant coefficients. Respondents living in the cities with higher share of secondary industry (c.f. share2nd) and with higher population density (c.f. pop_density) report lower WTP. Not always significant, people living in the cities enjoying higher economic growth rate seems to have higher WTP (c.f. gdp_growth). The key variables related to the five hypotheses are grouped together in the tables 13, where only the sign of the coefficients of the critical variables and their statistical significance are reported. According to our results, all the five hypotheses can be considered as valid, although the statistic significance of the results from DC2 data stays relatively low. As assumed in H1, the coefficients associated with the river water quality in the city where respondents live are found to be positive and significant in most of cases. This signifies that for a same river water quality improvement target, respondents do base their valuation of the project on the current water quality of their city, worse was the quality, higher will be their WTP. This finding, echoing to the results of Moore et al. (2012) and Tait et al. (2012), reveals the existence of the spatial scope sensitivity in CV studies. The LR test reported at the bottom of the tables 12.1-12.3 compares the global explanation power of models H2-H5 to that of H1. The related statistics reveal higher explanation power of the models including ⁄ ⁄ We tested both the and in our estimation and found that using ⁄ gave more coherent results. We can explain this by the following logic: compared to its upstream counter-partner, poorer a downstream city is, higher negotiation power will it has. This higher negotiation power will reduce the negative impact of upstream water pollution situation on the WTP of individual living in the downstream city. 1 the hypotheses H2-H5, confirm the necessity to include upstream city’s water quality into the WTP determination function. The inclusion of the upstream city’s river water quality (c.f. degu_upper), as expected in H2, is found to contribute negatively to the WTP and suggests a worse water quality in the direct upstream city can lead the WTP of people living in downstream city to decrease, all else being equal. This finding can be considered as an indirect evidence of the existence of transboundary pollution problem in Xijiang river basin. The adjustment of the upstream city’s river quality by distance (H3), negotiation power (H4) and both factors (H5) reveal quite stable and expected results. The inclusion of the into the product with upstream city water quality does not change neither the sign nor the significance of the coefficient of the upstream water quality related term, The negative coefficient before this cross-term confirms H3 that the negative externality of the transboundary pollution on WTP decreases with the distance from the upstream city. Very similar to the case of inclusion of distance adjustment term, the inclusion of each of the three measurement of the relative negotiation power between downstream and upstream cities, which are relative population size ( ; relative per capita GDP ( and relative GDP growth rate ( does not modify the negative coefficient before the variable of upstream city water quality, which therefore confirms H4 that if the downstream city possesses, compared to its direct upstream city, relatively larger negotiation power, measured by either a larger population size, a lower per capita GDP or a faster economic growth rate, a negatie externality of transboundary pollution on WTP will be weaker. The combination of the two dimensions of adjustment does not change the results, therefore also provides coherent confirmation for the H5. 9. Robustness check To test the robustness of the above-described negative externality of transboundary pollution in WTP determination, we use another three variables as substitute of the water quality of upstream city. The first one is the distance weighted sum of industrial output of all upstream cities along the Xijiang River. The reason to choose this variable is based on the fact that industrial wastewater emission is an important source of river water pollution and that the waste water emission is positively correlated with industrial output. For a respondent, without precise information about the pollution flowing from its upstream, it is natural to extrapolate it via the total industrial production scale along the upstream of the river. We can use total industrial output to measure it. At the same time, the autopurification function of the river will also allow the concentration of pollutant to decrease, we therefore use inverse distance ( ) as a weight to simulate the auto-purification procedure, where j (j=1,2, …,S) signifies all the cities located in the upstream of the river of city k. The industrial output variable used in the paper is therefore calculated as: ∑ S signifies the total number of upstream cities of the direct upstream city of city k. Parallel to the upstream pollution proxy related to industrial production scale, another important source of river water pollution is the everyday life waste water. We therefore also replace the upstream water quality by the distance weighted sum of population of all upstream cities along the Xijiang River. The distance weighted sum of population as proxy of upstream city water quality is therefore calculated as: ∑ The third substitute variable for upstream city water quality is the simple interger count numbers (1, 2,…) which indicate the total number of upstream cities along the Xijiang River before it flows through the city k, (stagek). stagek can be a good proxy of the negative externality related to transboudary river pollution for two reasons: firstly, given the water pollution concentration indicator’s cumulative nature, more cities located in the upstream of a river, more pollution will be accumulated in the river before it flow by the city k. Secondly, from the point of view of respondent, facing the risk of transboundary pollution, the probability for a water quality improvement project to be accomplished should also be dependant on the number of upstream cities: more cities located in the upstream of a river, more difficulties will it be to cooperate in controlling water pollution and higher will be risk of free-riding of upstream cities. The estimation results are listed in Table 14-16, where the sign of the key variables and their statistical significances are given. For details of the whole model estimation in each robustness test, please refer to the annex. We can see that the signs of coefficient of key substitute variables and their adjusted variants report quite similar and stable coefficients as in table 13. More specifically, weighted sum of industrial output/population and the stage both correlate negatively with respondents’ WTP, which reflect the impact of the negative externality of transboundary pollution on people’s WTP. Similar as the results in Table 13, this transboundary water pollution related externality also decreases with the distance and the negotiation power of the downstream cities, similar to our main finding. Therefore we can conclude that the three robust tests converge to the conclusion found in the last section. 10. Policy discussion The estimation results of the last section can be used to simulate the city-level average and aggregate WTP for the hypothetical water quality improvement project under two scenarios. We call the first one Business as Usual (BaU) in which we assume the transboundary pollution spillover between up and downstream cities affects directly a person’s WTP as revealed by our estimation models. The second scenario, to be named as Integrate, assumes the existence of an efficient river basin level water quality integrate management system which ensures a good collaboration between between up- and down-stream regions in river water pollution control, therefore removes concerns of the respondents about the negative externality caused by transboundary pollution spillover, so in this scenario, we suppose the coefficients related to the transboundary pollution to become zero. Table 17 and 18 report the simulation results for the 9 cities along the main tributary of the Xijiang river from Qujing until Zhuhai, upstream to downstream. In this paper, we use the estimation results of H5 where the relatively negotiation power measured by GDP growth rate ratio between upstream and downstream cities to calculate the mean WTP for each city.1 The comparison between the senarios BaU and Integrate reveals the average impact of transboundary river pollution spillover on average WTP and aggregate WTP for each city along the river. Clearly, if the concerns about transboundary spillover can be removed, the 1 The choice of the H5 estimation is based on its highest value of the Maximum Likelihood and LR test. mean WTP of a representative person in the downstream cities will be higher. Further downstream is the city located along the river, larger will be the increase in the mean WTP. Multiplying the mean WTP with the total population of corresponding city give the total WTP (c.f. Table 18). As we can see, the increase in the social benefit in the scenario Integrate compared to BaU can be quite big. Although the absolute values of social benefit increase of the project seems to be variables between different estimation models, the relative percentage increase is at about 10-62%, depending on the estimation models and approaches. The comparison of the aggregate WTP of these two scenarios actually reveals the potential social benefit that can be created by a river basin-level integrated water quality management system, which has already proven its efficiency in reducing river level transboundary pollution, based on international experiences in the Netherlands (Yu, 2011) and in Quebec (Fournier et al. 2013). Although the so-called River Basin Committees exist in China for most of the large rivers, these institutes are currently subordinate to the Ministry of Water Resource Management (MWRM) and only take care of region level water resource distribution but not the transboundary pollution problems. Similar as the local environmental protection office, this committee is not financially self-dependent. Their subordinate relationship with respect to local government reduces largely their efficiency in reducing the transboundary negative externality in either the inter-region water resource distribution or river water pollution (Yu, 2011). The huge social net benefice revealed by our study actually indicates that it is financial viable to empower the river basin committees with more transboundary river pollution control responsibilities. Our simulation results about the net social benefit of integrate water quality management system can also provide interesting insight for the currently hotly debated mechanism of Payment for Ecological Service (PES) (Wang, 2004, XXX, XXX), whose idea is currently tested via several pilot projects in several trans-province level large water bodies, such as Taihu Lake (Jiangsu and Zhejiang Province) and Xin’anjiang River (Anhui and Zhejiang province), etc. Concretely, PES aims at ensuring the payment made by people/regions located in downstream to the people/regions located in upstream of river for their efforts/sacrifices to assure better river-related ecological services, either in terms of concrete water quality protection measures or in terms of real water pollutant abatement. Such a payment mechanism, either ensured by bilateral or multilateral transboundary agreements 1 or by a river basin committee, provides a potentially feasible remedy for the market failure caused by river transboundary pollution spillover by compensating the environmental protection efforts of upstream regions. From this angle, our estimations of the total social benefit differences between the BaU and integrate water quality management scenarios provide an upper bound for the amount that a downstream regional is willing to pay for the effort exerted by the upstream regions to ensure the river not to be additionally polluted by their activities. 1 Such agreements exist already between certains provinces, good examples are the one between the province of Zhejiand and Jiangsu for Taihu Lake, XXX for Heihe River, etc. (Zhao et al. 2013, Yu, 2011, etc.) 11. Conclusion This paper uses contingent valuation method to assess the economic benefits of water quality improvement project of Xijiang river basin in southern China and gives a detailed analysis on how the transboundary river pollution spillover can affect people’s willingness to pay for a river water quality improvement project. Our results suggest that besides the individual-level characteristics and city-level economic and initial environmental conditions, the spatial location of the cities along the river with respect to the other cities also exerts significant influence on people’s WTP for water improvement project. Precisely, our results reveal that worse is the pollution in the direct upstream city, lower will be the WTP of the people living in the direct downstream, all else being equal. This WTP diminishing effect is also found to be adjustable by distance between the direct up and downstream cities and by the relative negotiation power of the downstream city with respect to its direct upstream peer. These findings reveal another pertinent dimension of spatial factors, which is the interrelationship between regions and their impact on the benefits that each region can enjoy from environmental quality improvement. Although we can consider our results as an indirect proof about the existence of the negative externality caused by transboundary river pollution spillover for the case of China, we admit that it is still necessary to provide direct transboundary water pollution evidence for the case of China, especially for the discussion of the necessity about establishing a river-basin level water management system in China. Previous similar studies are Sigman (2002, 2005) and unpublished working paper of Lipscomb and Mobarak (2007). To conduct such a study, detailed and reliable water quality data from the monitoring station along the Xijiang River and their location with respect to different the regional boundaries will be necessary. Following the logic of a cost-benefit analysis, our result of the net benefit gain via an integrate basin level water quality management system can also be compared with the potential economic cost/loss that different regions/cities along the river need to bear to respect the uniform water quality targets. The existing theoretical analysis as Van der Laan and Moes (2012) and Ni and Wang (2002) seem to confirm a net gain in social benefit. Although such a comparison is not possible for the current study since we do not have information about the related economic cost/loss of different regions along the river, the provision of the information about the potential gain in our paper offers such a possibility of comparison for future studies. Reference Bateman, I.J.(2009. 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CSERGE working paper EDM, No. 09-01. Fig 1 Map of Xijiang River Basin Table 1 Alternative Bids for the CVM survey B Bl Bu 3 0 5 5 3 10 10 5 15 15 10 20 20 15 30 30 20 50 50 30 80 80 50 150 150 80 200 200 150 300 300 200 500 500 300 1000 Note: B is the initial bid(monthly voluntary donate, in Chinese Yuan);Bl is second bid if response to first bid was “no”; B u is second bid if response to first bid was “yes” Table 2. Matrix used in MBDC WTP question Price (Yuan) Free 3 5 10 15 20 30 50 80 150 200 300 500 1000 Definitely not Probably not Not sure Probably yes Definitely yes Table 3 City Level Sampling Detail City/region Guangzhou Shengzhen Dongguan Fuoshan Guiling Nanning Kunming Qujing Guiyang Guigang Zhaoqing Liuzhou Baise Qiannan Zhongshan Wuzhou Qianxinan Yunfu Yuxi Zhuhai Total Population (million) 12.7 10.4 8.2 7.2 7.0 6.7 6.4 5.9 4.3 4.1 3.9 3.8 3.5 3.2 3.1 2.9 2.8 2.4 2.3 1.6 108.7 Sample Size (DC) 132 120 84 72 72 72 72 48 48 48 48 36 36 36 36 36 36 24 24 24 1104 Sample size (MBDC) 140 114 90 79 76 73 71 64 47 45 43 41 38 35 34 31 30 26 25 17 1119 Table 4 Respondents information of MBDC and DC questionnaires MBDC Variable Description mean age The age of respondents 33.27 edu The years of education the respondents has acquired 14.57 income_level The monthly income of respondents(Yuan) 4101.88 gender Gender of respondents(1=male,0=female) 0.54 N 1043 ***p<0.01,**p<0.05,*p<0.1,Kruskal-Wallis Test's chi-squared Value DC mean KW-test 33.96 1.839 13.78 21.579*** 4585.44 1.958 0.52 0.459 1090 Table 5 Comparisons of socio-economic statistics of respondent across provinces Guangdong Sample Census Guangxi Sample Census Gender Female 49.03% 47.38% 49.60% 48.90% Male 50.97% 52.62% 50.40% 51.10% Education years 0 0.90% 1.38% 1.00% 1.56% 6 0.00% 16.38% 0.00% 17.08% 9 8.70% 42.64% 14.50% 35.68% 12 23.30% 24.78% 25.60% 25.41% 16+ 67.00% 14.81% 59.00% 20.27% Age 20-29 45.86% 34.20% 55.87% 27.15% 30-39 29.95% 27.07% 22.50% 25.22% 40-49 13.82% 19.72% 12.81% 21.36% 50-59 8.38% 9.67% 6.14% 13.37% 60+ 1.99% 9.17% 2.69% 12.88% Data source: Tabulation On The 2010 Population Census Guangxi Province, Yunnan Province Guizhou Sample Census Yunnan Sample Census 42.92% 57.08% 49.10% 50.90% 37.63% 62.37% 49.15% 50.85% 0.90% 0.00% 8.40% 31.90% 58.80% 3.32% 22.56% 34.71% 19.65% 19.75% 0.00% 20.20% 8.00% 29.60% 42.10% 2.99% 22.83% 32.18% 20.90% 21.11% 40.49% 30.94% 20.04% 7.30% 1.34% Of Guizhou 26.31% 23.48% 24.42% 25.91% 31.27% 25.83% 21.05% 31.27% 22.90% 12.55% 12.59% 12.37% 14.10% 1.49% 14.45% Province, Guangdong Province, Table 6. WTP answer data cleaning details Category Definition 1 2 3 4 5 6 WTP value covered by bid price range from 0 to 1000yuan Negative response at zero bid Positive response at highest bid (1000 yuan per month) Missing values Disordered answers Total number Number of respondents DC MBDC 684 847 119 143 99 37 120 1 1023 63 non-applicable 1090 Table 7 Statistics of No demand MBDC Number of respondents Reasonable answers It is not important to improve the water quality and ecological environment This kind of donation will put a heavy burden to my family Others: Have little chance to get in touch with the river Protest answers I don't believe this hypothetic fund will be used properly Others: Government should take this responsibility DC % Number of respondents % 1 0.096 4 0.4 14 1.34 56 5.1 2 0.19 1 0.1 87 8.3 76 6.97 15 1.44 6 0.55 Table 8 Statistics of Extremely High Responses MBDC Number of respondents Reasonable high demand I can afford 1000yuan per month for environmental protection It is very important to protect water resource in this town I want to make some contribution to environmental protection Unreliable high demand I am kidding Other(1000>one-tens of her or his monthly income) DC % Number of respondents % 5 0.479 0 0 8 0.77 0 0 13 1.25 2 0.183 31 3 9 0.826 42 4.03 26 2.385 Table 9 The distribution of answers in MBDC questionnaires Bid Price 0 3 5 10 15 20 30 50 80 150 200 300 500 1000 Def yes 92.6% 78.6% 70.8% 56.5% 38.7% 32.5% 26.8% 17.1% 9.2% 3.3% 1.2% 0.3% 0.1% 0.0% Prob yes 4.8% 14.7% 17.3% 22.2% 23.2% 18.1% 14.7% 15.0% 12.4% 6.2% 2.7% 1.1% 0.3% 0.0% Not sure 2.5% 1.9% 4.7% 7.5% 13.7% 15.8% 13.0% 13.0% 15.0% 11.1% 7.9% 4.7% 2.4% 0.4% Prob not 0.0% 1.6% 2.5% 5.2% 6.8% 9.8% 12.0% 11.4% 11.6% 13.1% 13.0% 11.9% 8.2% 4.4% Def not 0.0% 3.2% 4.7% 8.6% 17.7% 23.8% 33.5% 43.5% 51.7% 66.3% 75.2% 82.1% 89.0% 95.2% Table 10. Cumulative bid acceptance response rate for the 12 initial bid amounts (shown in bold type) and corresponding double-bound trees in DC2 WTP question → 3 5 10 15 20 30 50 80 150 200 300 500 0 3 5 10 15 20 30 50 80 150 200 300 500 1000 95.7% 88.2% 80.7% 80.6% 78.4% 87.4% 64.8% 81.1% 77.5% 70.5% 67.4% 75.9% 58.4% 65.5% 70.8% 51.7% 59.6% 59.1% 40.4% 48.4% 52.2% 33.3% 34.8% 43.3% 19.6% 18.9% 41.8% 13.3% 28.6% 32.3% 13.2% 23.7% 27.3% 14.0% 15.9% 8.0% First row of this table gives the initial bid prices, and the first column gives the corresponding bid price. Table 11. Descriptive statistics Varibles Description 1. Individual level variables Environmental perception Eco_imp Economics development is more important than Environmental protection(0=no,1=yes) rep_gov Government should take the responsibility in environmental protection(0=no,1=yes) water_problem Water pollution is very serious in this region (0=no,1=yes) Willingness to services for environmental protection program:5=definitely yes,4=probably yes,3=not will_service sure,2=probably not,1=definitely no quality_imp quality of xijiang improved in the last three years quality_deg quality of xijiang degraded in the last three years Confidence of quality impovement:4=Fully achieved,3=have a high probability of being achieved,2=probably confidence cannot be achieved,1= cannot be achieved Socio-economics factors Income changing with water quality improvement:5=Increasing greatly,4=Increasing,3=no income_willchange change,2=decreasing,1=Decreasing greatly age age edu 0=no,6=primary school,9=middle school,12=high school,16=college,19=graduate school+ income_level Income, the income level has been subsituted with the local average wages of staff and workers(1000 Yuan) mdaily_2 Respondents' income can only meet the needs of food(1=yes,0=no) mdaily_3 Respondents' income can can cover the basic neccesity?(1=yes,0=no) mdaily_4 Respondents' income can meet the needs of their daily life?(1=yes,0=no) gender Dummy for Male(0=female,1=male) d_add2 Near the river but cannot see it directly d_add3 Far away from the river d_fish The frequency of eating freshwater fishes (1=a least once a month,0=other wise) 2. City level macro-variables share2nd_mean The share of secondary sector in gross regional output pop_density Population density of sampled city gdp_growth_mean Gdp growth rate of sampled city 3. Spatial related variables degree The level of water quality degree_upper The level of water quality of the upper stream city stage A variable that record how many cities locate a city’s upstream distance Distance between sample city and its upper stream city gdppc_vs The comparison of gdp per capita between sampled city and its upstream city, which measured as GDPPC of upstream city/GDPPC of sampled city pop_vs The comparison of population between sampled city and its upstream city, which measured as Population of upstream city/Population of sampled city gdpgwru_vs The comparison of gdp growth rate between sampled city and its upstream city, which measured as gdp growth rate of upstream city/ gdp growth rate of sampled city dum_ups This city located on the upstream of Xijiang river(0=no,1=yes) dum_mds This city located on the mid-stream of Xijiang river(0=no,1=yes) Ind_output Aggregate industrial output of all upstream cities (weithed by distance) Variable 1 for Robustness check Stage Number of cities in the upstream part of the river: Variable 2 for Robustness check N MBDC DC2 mean sd mean sd 0.60 0.73 0.60 0.49 0.44 0.49 0.59 0.72 0.67 0.49 0.45 0.47 3.90 0.94 3.93 0.99 0.23 0.36 0.42 0.48 0.23 0.43 0.42 0.50 2.19 1.09 2.06 1.06 2.68 1.33 2.73 1.32 34.09 14.56 4.44 0.07 0.62 0.25 0.51 0.32 0.57 0.79 10.94 3.13 4.10 0.26 0.48 0.43 0.50 0.47 0.50 0.41 34.64 13.73 4.71 0.08 0.62 0.23 0.52 0.31 0.58 0.77 11.03 3.53 4.87 0.26 0.49 0.42 0.50 0.46 0.49 0.42 48.15 17.53 14.06 9.51 13.10 1.62 48.62 16.19 14.02 9.44 12.97 1.67 3.80 2.17 2.57 1.06 0.85 1.51 1.86 2.71 1.64 1.57 3.73 2.00 2.35 1.04 0.81 1.57 1.86 2.63 1.62 1.60 0.53 0.71 0.53 0.76 0.68 0.54 0.63 0.54 0.36 0.18 83.58 2.57 0.48 0.39 146.89 2.71 0.38 0.22 67.59 2.35 0.48 0.42 131.26 2.63 727 910 Table 12.1 Estimation results with spatial factors, MBDC data, Welsh and Poe (1998) approach, “probably yes” model Bid price rep_gov water_problem will_service quality_deg age education income_level Income significant higher than need male Can see the river Far from the river d_fish share2nd pop_density gdp_growth degree H1 -0.016 (36.10)*** -0.310 (3.45)*** 0.027 (0.34) 0.169 (4.09)*** 0.305 (3.77)*** -0.003 (0.95) 0.002 (0.12) 0.039 (3.62)*** 0.371 (3.79)*** 0.026 (0.34) -0.163 (1.22) -0.191 (1.51) 0.180 (1.89)* -0.005 (1.21) -0.022 (5.59)*** 0.057 (2.31)** 0.137 (4.11)*** degree_upper H2 -0.017 (36.10)*** -0.321 (3.57)*** 0.083 (1.03) 0.143 (3.42)*** 0.309 (3.82)*** -0.001 (0.40) 0.000 (0.02) 0.036 (3.29)*** 0.389 (3.96)*** 0.025 (0.33) -0.153 (1.15) -0.194 (1.53) 0.161 (1.69)* -0.015 (3.20)*** -0.012 (2.84)*** 0.084 (3.30)*** 0.142 (4.27)*** -0.123 (4.53)*** H3 -0.017 (36.09)*** -0.314 (3.48)*** 0.093 (1.17) 0.139 (3.32)*** 0.275 (3.39)*** -0.002 (0.52) 0.002 (0.16) 0.040 (3.65)*** 0.378 (3.85)*** 0.024 (0.31) -0.143 (1.07) -0.175 (1.38) 0.163 (1.71)* -0.019 (3.75)*** -0.007 (1.59) 0.062 (2.52)** 0.156 (4.65)*** -0.239 (5.30)*** degu_pop H4 -0.017 (36.10)** -0.313 (3.48)** 0.034 (0.43) 0.154 (3.69)** 0.296 (3.65)** -0.003 (0.81) -0.001 (0.10) 0.039 (3.57)** 0.387 (3.95)** 0.010 (0.14) -0.148 (1.11) -0.199 (1.57) 0.167 (1.75) -0.006 (1.31) -0.019 (4.75)** 0.044 (1.76) 0.133 (3.99)** Prob Yes (727 obs) H4 -0.017 (36.11)** -0.278 (3.08)** 0.059 (0.75) 0.153 (3.68)** 0.276 (3.40)** -0.001 (0.17) 0.000 (0.02) 0.039 (3.63)** 0.374 (3.81)** 0.025 (0.32) -0.089 (0.67) -0.151 (1.19) 0.199 (2.08)* -0.003 (0.63) -0.008 (1.67) 0.064 (2.59)** 0.101 (2.99)** -0.065 (2.79)** degu_gdppc Log likelihood LR Mean WTP KR CI Ratio H5 -0.017 (36.10)** -0.316 (3.51)** 0.052 (0.65) 0.146 (3.48)** 0.293 (3.62)** -0.003 (0.81) -0.002 (0.15) 0.039 (3.58)** 0.390 (3.97)** 0.010 (0.13) -0.154 (1.16) -0.198 (1.56) 0.153 (1.60) -0.011 (2.42)* -0.015 (3.65)** 0.034 (1.34) 0.153 (4.56)** -0.072 (5.43)** -0.557 (1.07) -2202.27 52.68 [48.00 57.48] 0.18 -0.292 (0.56) -2192.02 20.50 (0.000)*** 52.69 [48.56 57.02] 0.16 0.023 (0.04) -2188.23 28.08 (0.000)*** 52.71 [48.60 57.03] 0.16 -0.017 (36.10)** -2198.39 7.77 (0.01)** 52.67 [49.57 57.43] 0.15 H5 -0.017 (36.09)** -0.323 (3.58)** 0.092 (1.15) 0.137 (3.26)** 0.295 (3.64)** -0.002 (0.44) 0.001 (0.08) 0.039 (3.57)** 0.384 (3.91)** 0.017 (0.23) -0.151 (1.13) -0.193 (1.52) 0.166 (1.75) -0.018 (3.75)** -0.010 (2.24)* 0.072 (2.91)** 0.147 (4.41)** H5 -0.017 (36.09)** -0.316 (3.51)** 0.099 (1.23) 0.135 (3.22)** 0.266 (3.28)** -0.002 (0.62) 0.003 (0.27) 0.043 (3.93)** 0.371 (3.79)** 0.016 (0.21) -0.146 (1.09) -0.177 (1.40) 0.176 (1.85) -0.021 (4.05)** -0.007 (1.56) 0.051 (2.05)* 0.160 (4.78)** -0.198 (3.90)** degu_gdpgwr Constant H4 -0.017 (36.09)** -0.323 (3.58)** 0.092 (1.15) 0.137 (3.26)** 0.295 (3.64)** -0.002 (0.44) 0.001 (0.08) 0.039 (3.57)** 0.384 (3.91)** 0.017 (0.23) -0.151 (1.13) -0.193 (1.52) 0.166 (1.75) -0.018 (3.75)** -0.010 (2.24)* 0.072 (2.91)** 0.147 (4.41)** -0.730 (1.40) -2187.5 29.55 (0.006 )** 52.7 [49.66 57.37] 0.15 -0.131 (5.39)** -0.131 (5.39)** -0.017 (36.09)** -2187.71 29.12 (0.007)** 52.7 [49.62 57.37] 0.15 0.194 (0.35) -2194.67 15.21 (0.000)*** 52.69 [49.61 57.41] 0.15 0.013 (0.03) -2184.81 34.92 (0.000)*** 52.72 [49.66 57.36] 0.15 -0.211 (5.58)** 0.253 (0.47) -2186.68 31.19 (0.000)*** 52.71 [49.65 57.37] 0.15 Table 12.2 Estimation results with spatial factors, MBDC data, approach Wang and He (2011) Bid price rep_gov water_problem will_service quality_deg age education income_level Income significant higher than need male Can see the river Far from the river d_fish share2nd pop_density gdp_growth degree H1 -0.011 (38.13)*** -18.436 (2.19)** 7.080 (0.95) 15.093 (3.87)*** 20.245 (2.67)*** -0.271 (0.79) -0.554 (0.46) 4.019 (3.96)*** 27.176 (2.96)*** -5.829 (0.81) -25.250 (2.02)** -28.295 (2.38)** 10.770 (1.20) -0.917 (2.29)** -1.011 (2.83)*** 9.605 (4.16)*** 5.134 (1.65)* degree_upper H2 -0.011 (38.13)*** -18.666 (2.22)** 9.700 (1.29) 13.791 (3.51)*** 20.217 (2.68)*** -0.177 (0.51) -0.614 (0.51) 3.825 (3.76)*** 27.677 (3.03)*** -5.859 (0.81) -24.755 (1.98)** -28.315 (2.39)** 9.815 (1.10) -1.383 (3.06)*** -0.580 (1.43) 10.790 (4.57)*** 5.264 (1.69)* -5.574 (2.22)** H3 -0.011 (38.13)*** -18.159 (2.17)** 10.930 (1.46) 13.203 (3.37)*** 18.151 (2.41)** -0.178 (0.52) -0.534 (0.44) 3.988 (3.95)*** 27.058 (2.97)*** -5.975 (0.83) -24.015 (1.93)* -27.186 (2.30)** 9.611 (1.08) -1.670 (3.63)*** -0.186 (0.43) 9.831 (4.29)*** 5.990 (1.93)* -13.564 (3.24)*** degu_pop H4 -0.011 (38.13)** -18.419 (2.19)* 7.360 (0.99) 14.454 (3.68)** 19.812 (2.62)** -0.250 (0.73) -0.674 (0.56) 3.986 (3.93)** 27.725 (3.02)** -6.473 (0.89) -24.656 (1.97)* -28.562 (2.40)* 10.217 (1.14) -0.933 (2.33)* -0.899 (2.43)* 9.077 (3.86)** 4.926 (1.58) Wang &He, 727 obs. H4 H4 -0.011 -0.011 (38.13)** (38.13)** -16.188 -18.709 (1.93) (2.24)* 9.038 11.104 (1.22) (1.49) 14.014 12.935 (3.61)** (3.31)** 17.902 19.221 (2.37)* (2.56)* -0.107 -0.154 (0.31) (0.45) -0.618 -0.591 (0.51) (0.49) 3.977 3.928 (3.94)** (3.90)** 26.846 27.369 (2.95)** (3.01)** -5.859 -6.354 (0.82) (0.89) -20.947 -24.429 (1.68) (1.97)* -25.531 -28.166 (2.16)* (2.39)* 11.561 9.763 (1.30) (1.10) -0.831 -1.710 (2.09)* (3.74)** -0.207 -0.285 (0.48) (0.69) 10.168 10.452 (4.42)** (4.54)** 2.919 5.525 (0.92) (1.79) -2.623 (1.20) degu_gdppc -3.485 (3.36)** Log likelihood LR Mean WTP KR CI Ratio -62.418 (1.27) -4344.03 75.99 [68.89 83.48] 0.19 -49.903 (1.01) -4341.58 4.09 (0.0268)** 75.99 [69.54 82.95] 0.18 -28.804 (0.58) -4338.81 10.45 (0.0012)*** 75.99 [69.56 82.93] 0.18 -46.849 (0.92) -4343.31 1.44 (0.230) 75.99 [71.13 83.46] 0.16 H5 -0.011 (38.13)** -17.117 (2.04)* 10.162 (1.36) 13.821 (3.55)** 17.539 (2.32)* -0.149 (0.44) -0.539 (0.45) 3.925 (3.89)** 27.116 (2.98)** -5.643 (0.78) -22.824 (1.83) -26.206 (2.21)* 9.805 (1.10) -1.362 (3.22)** -0.033 (0.07) 10.175 (4.42)** 5.080 (1.64) H5 -0.011 (38.13)** -18.206 (2.19)* 12.074 (1.62) 12.520 (3.21)** 17.078 (2.27)* -0.182 (0.54) -0.440 (0.37) 4.186 (4.17)** 26.535 (2.93)** -6.558 (0.92) -23.950 (1.93) -27.104 (2.30)* 10.231 (1.15) -1.955 (4.17)** 0.002 (0.00) 9.086 (3.97)** 6.469 (2.09)* -9.626 (2.03)* degu_gdpgwr Constant H5 -0.011 (38.13)** -18.459 (2.20)* 8.299 (1.11) 13.867 (3.53)** 19.499 (2.58)** -0.244 (0.71) -0.728 (0.60) 3.976 (3.92)** 27.845 (3.04)** -6.636 (0.92) -24.793 (1.98)* -28.521 (2.40)* 9.368 (1.04) -1.194 (2.83)** -0.693 (1.78) 8.467 (3.57)** 5.814 (1.86) -71.629 (1.47) -4338.43 11.2 (0.000) *** 75.99 [71.16 83.41] 0.16 -7.204 (3.11)** -7.859 (3.51)** -27.422 (0.55) -4337.92 12.22 (0.000)*** 75.99 [71.16 83.41] 0.16 -25.586 (0.49) -4341.97 4.12 (0.000)*** 75.99 [71.14 83.45] 0.16 -52.718 (1.08) -4339.21 9.64 (0.000)** 75.99 [71.15 83.42] 0.16 -14.444 (4.15)** -6.201 (0.12) -4335.54 16.99 (0.000)*** 75.99 [71.18 83.38] 0.16 Table 12.3 Estimation results with spatial factors, DC2 data, Double-bound methods (Hanemann 1991 approach) Bid price rep_gov water_problem will_service quality_deg age education income_level Income significant higher than need male Can see the river Far from the river d_fish share2nd pop_density gdp_growth degree H1 -0.008 (23.33)*** -0.236 (2.34)** -0.014 (0.15) 0.355 (7.57)*** 0.235 (2.55)** -0.003 (0.65) -0.009 (0.70) 0.059 (4.98)*** 0.202 (1.82)* -0.060 (0.69) -0.239 (1.53) -0.169 (1.17) 0.187 (1.76)* -0.004 (0.89) -0.002 (0.48) -0.019 (0.70) 0.137 (3.85)*** degree_upper H2 -0.008 (23.39)*** -0.236 (2.35)** -0.013 (0.14) 0.354 (7.50)*** 0.236 (2.55)** -0.003 (0.64) -0.009 (0.69) 0.059 (4.98)*** 0.202 (1.83)* -0.060 (0.68) -0.238 (1.52) -0.166 (1.12) 0.187 (1.75)* -0.005 (0.86) -0.002 (0.38) -0.019 (0.66) 0.137 (3.85)*** -0.003 (0.10) H3 -0.008 (23.42)*** -0.239 (2.38)** -0.008 (0.09) 0.350 (7.38)*** 0.233 (2.53)** -0.003 (0.64) -0.008 (0.63) 0.060 (5.01)*** 0.208 (1.88)* -0.059 (0.67) -0.227 (1.45) -0.141 (0.94) 0.179 (1.67)* -0.006 (1.13) 0.000 (0.03) -0.018 (0.66) 0.141 (3.90)*** -0.041 (0.76) degu_pop H4 -0.008 (23.34)** -0.232 (2.29)* -0.013 (0.14) 0.357 (7.55)** 0.234 (2.54)* -0.003 (0.62) -0.009 (0.72) 0.059 (4.97)** 0.201 (1.82) -0.060 (0.68) -0.244 (1.56) -0.176 (1.21) 0.191 (1.78) -0.004 (0.85) -0.002 (0.53) -0.018 (0.67) 0.138 (3.86)** Double Bound (910 obs.) H4 H4 -0.008 -0.008 (23.33)** (23.52)** -0.236 -0.238 (2.35)* (2.36)* -0.012 -0.012 (0.13) (0.12) 0.351 0.352 (7.41)** (7.46)** 0.240 0.236 (2.59)** (2.56)* -0.003 -0.003 (0.64) (0.65) -0.008 -0.009 (0.64) (0.68) 0.059 0.060 (4.97)** (5.00)** 0.206 0.204 (1.86) (1.84) -0.061 -0.059 (0.70) (0.67) -0.229 -0.234 (1.46) (1.49) -0.152 -0.156 (1.03) (1.05) 0.185 0.184 (1.74) (1.73) -0.004 -0.005 (0.84) (0.96) -0.000 -0.001 (0.06) (0.25) -0.018 -0.018 (0.66) (0.65) 0.135 0.138 (3.74)** (3.86)** 0.010 (0.41) degu_gdppc -0.009 (0.67) Log likelihood LR Mean WTP KR CI Ratio -0.516 (0.89) -1045.41 103.43 [92.41 114.66] 0.22 -0.513 (0.89) -1045.40 0.01 (0.9170) 103.42 [93.64 113.89] 0.20 -0.457 (0.79) -1045.11 0.58 (0.4450) 103.42 [93.65 113.83] 0.20 -0.557 (0.95) -1045.32 0.17 (0.681) 103.44 [95.09,114.92] 0.19 H5 -0.008 (23.27)** -0.237 (2.36)* -0.012 (0.13) 0.352 (7.41)** 0.235 (2.55)* -0.003 (0.64) -0.009 (0.66) 0.060 (4.99)** 0.205 (1.85) -0.060 (0.69) -0.232 (1.48) -0.155 (1.04) 0.184 (1.72) -0.005 (0.96) -0.001 (0.12) -0.019 (0.67) 0.138 (3.86)** H5 -0.008 (23.30)** -0.240 (2.39)* -0.007 (0.08) 0.348 (7.35)** 0.229 (2.48)* -0.003 (0.65) -0.008 (0.60) 0.060 (5.03)** 0.211 (1.90) -0.059 (0.67) -0.225 (1.43) -0.133 (0.88) 0.177 (1.65) -0.007 (1.23) 0.001 (0.12) -0.020 (0.72) 0.142 (3.93)** -0.028 (0.48) degu_gdpgwr Constant H5 -0.008 (23.52)** -0.241 (2.38)* -0.012 (0.13) 0.351 (7.40)** 0.233 (2.53)* -0.003 (0.66) -0.009 (0.66) 0.060 (5.00)** 0.204 (1.84) -0.061 (0.69) -0.232 (1.48) -0.157 (1.06) 0.182 (1.70) -0.005 (0.99) -0.001 (0.29) -0.021 (0.76) 0.140 (3.87)** -0.539 (0.93) -1045.18 0.45 (0.502) 103.4 [94.93,114.86] 0.19 -0.012 (0.40) -0.011 (0.38) -0.488 (0.84) -1045.33 0.15 (0.701) 103.41 (94.93,114.81) 0.19 -0.445 (0.75) -1045.29 0.23 (0.634) 103.44 (95.09,114.92) 0.19 -0.510 (0.88) -1045.33 0.16 (0.692) 103.43 (94.97,114.85) 0.19 -0.044 (0.95) -0.408 (0.69) -1044.96 0.9 (0.343) 103.43 (95.01,114.87) 0.19 Table 13 Summary table for the five hypotheses related to the spatial aspect related to transboundary pollution Def Yes +*** Prob Yes +*** Not Sure + Wang &He +* Single Bound +*** Double Bound +*** degree Degree_upper +*** -*** +*** -*** + -* +* -** +*** - +*** - H3 degree Degree_upper_dist +*** -*** +*** -*** +* -*** + -*** +*** - +*** - H4 degree Degree_upper_pop degree Degree_upper_gdppc degree Degree_upper_gdpgwr +** -** +** -** +** -** +** -** +** -** +** -** + + -** + -** + + -** +* -*** +** + +** +** - +** + +** +** - degree Degree_upper_pop_dist degree Degree_upper_gdppc_dist degree Degree_upper_gdpgwr_dist +** -** +** -** +** -** +** -** +** -** +** -** + + -* + -** + -* + -** +* -** +** +** +** - +** +** +** - Variables degree H2 H1 H4 H4 H5 H5 H5 Table 14. Robustness check 1: upstream city water quality replaced by the sum of weighted industrial output of all upstream cities Def Yes Prob Yes Not Sure Variables Degree +*** +*** H2 Degree Ind_out _upper +*** -** H3 Degree Ind_out _upper_dist H4 H1 H4 H4 H5 H5 H5 + Wang &Jie +* Single Bound +*** Double Bound +*** +*** -*** +* -*** +* -*** +*** -* +*** - +*** -** +*** -*** +** -*** +** -*** +*** -** +*** -** Degree Ind_out _upper_pop Degree Ind_out _upper_gdppc Degree Ind_out _upper_gdpgwr +** -** +** -** +** -** +** -** +** -** +** -** + -* + -** +* -** +* -* + -** +* -** +** + +** + +** + +** + +** + +** + Degree Ind_out _upper_pop_dist Degree Ind_out _upper_gdppc_dist Degree Ind_out _upper_gdpgwr_dist +** -** +** -*** +** -** +** -** +** -** +** -** +* -** +* -*** +* -** +* -** +* -** +* -** +** +** +** - +** +** +** - Table 15. Robustness check 2 : upstream water quality replaced by the sum of weighted population of all upstream cities Def Yes Prob Yes Not Sure + Wang & He +* Single Bound +*** Double Bound +*** +*** -*** + -*** + -*** +*** -** +*** - +*** -*** +*** -*** +* -*** +** -*** +*** -** +*** -* Degree Tot_pop _upper_pop Degree Tot_pop _upper_gdppc Degree Tot_pop _upper_gdpgwr +*** -*** +*** -*** +*** -*** +*** -*** +*** +*** -*** + -** + + -*** + -** +* + + -*** +*** +*** +*** -** +** +** +** - Degree Tot_pop _upper_pop_dist Degree Tot_pop _upper_gdppc_dist Degree Tot_pop _upper_gdpgwr_dist +*** -*** +*** -*** +*** -*** +*** -*** +*** -*** +*** -*** +* -*** +*** -** + -*** +** -*** +*** -*** +*** -*** +*** -** +*** -* +*** -** +** +** +** -* Variables Degree +*** +*** H2 Degree Tot_pop _upper +*** -*** H3 Degree Tot_pop _upper_dist H4 H1 H4 H4 H5 H5 H5 Table 16. Robustness check 3 : upstream water quality replaced by number of upstream cities Def Yes Prob Yes Not Sure + Wang & He +* Single Bound +*** Double Bound +*** +** -*** + -*** +* -*** +*** -** +*** -* +*** -*** +** -*** + -*** +*** -*** +*** -*** +*** -** Degree stage _upper_pop Degree stage _upper_gdppc Degree stage _upper_gdpgwr +** -** +** +** -*** +** -** +** +** -** + -* + + -** +** -** +** -*** +** -*** +** -* +** +** -* +** +** +** - Degree stage _upper_pop_dist Degree stage _upper_gdppc_dist Degree stage _upper_gdpgwr_dist +** -** +** -** +** -** +** -** +** -** +** -** + -* + -** + -** +** -*** +** -*** +** -*** +** -** +** -* +** -** +** -* +** -* +** -* Variables Degree +*** +*** H2 Degree stage _upper +*** -*** H3 Degree stage _upper_dist H4 H1 H4 H4 H5 H5 H5 Table 17. Estimated Mean WTP in Spatial model and Constrained Model (CNY per month) Tributary location (up to Def Yes downstream) City/Region BaU Integrate Prob Yes BaU Wang&He Not Sure Integrate BaU 1 Qujing 37.7 37.7 55.2 55.2 70.8 1 Yuxi 38.9 38.9 53.9 53.9 91.3 96.7 Integrate BaU 70.8 61.5 52.1 52.1 169.9 176.8 Single Integrate BaU Double Integrate BaU Integrate 61.5 133.9 133.9 116.1 116.1 45.1 45.1 179.9 179.9 130.6 130.6 136.4 142.6 128.1 132.2 82.9 85.2 2 Qianxinan 40.8 44.6 2 Guigang 22.7 29.1 51.5 60.7 98.4 110.1 78.1 88.7 101.5 108.6 74.7 78.6 52.4 60.1 83.6 93.4 70.0 78.9 61.1 67 60.3 63.6 3 Wuzhou 31.4 36.8 4 Yunfu 13.2 27.8 19.2 40 25.1 51.6 20.5 44.4 111.3 127.3 91.3 100.1 44.2 62.5 95.2 118.5 75.1 96.2 51.4 65.4 47.2 55 5 Zhaoqing 16.4 29.2 6 Foshan 13.1 21.6 38.2 50.2 81.4 96.7 64.9 78.8 79.3 88.6 53.9 59 36.7 86.4 78.1 141.5 63.6 120.9 139.0 177.2 109.6 130.9 27.8 42.2 29.8 48.1 29.3 45.9 72.1 83.2 69.5 75.6 42.8 63.7 36.3 55.1 108.2 120.7 86.1 93.1 78.1 103.6 64.1 87.1 109.8 125.2 87 95.5 7 Zhongshan 16.9 51.9 8 Guangzhou 16.4 26.5 Zhuhai 21.7 33.2 36.7 53.1 Average WTP 22.7 36.7 44.5 64.5 9 Mean WTP Table 18. Estimated Total WTP in Spatial model and Constrained Model (Million CNY per month) Tributary (up to downstream) 1 1 2 2 3 4 5 6 7 8 9 Def Yes Prob Yes Not Sure Wang&Jie Single Double City/Region BaU Integrate BaU Integrate BaU Integrate BaU Integrate BaU Integrate BaU Integrate Qujing Yuxi Qianxinan Guigang Wuzhou Yunfu Zhaoqing Foshan Zhongshan Guangzhou Zhuhai 241.28 241.28 353.28 353.28 453.12 453.12 393.6 393.6 856.96 856.96 743.04 743.04 89.47 89.47 123.97 123.97 119.83 119.83 103.73 103.73 413.77 413.77 300.38 300.38 114.24 124.88 255.64 270.76 475.72 495.04 381.92 399.28 358.68 370.16 232.12 238.56 86.26 110.58 195.7 230.66 373.92 418.38 296.78 337.06 385.7 412.68 283.86 298.68 91.06 106.72 151.96 174.29 242.44 270.86 203 228.81 177.19 194.3 174.87 184.44 34.72 53.12 58.72 84.96 68.48 101.92 58.08 88.16 173.12 193.12 137.76 148.96 Total WTP 1112.46 1803.45 2185.04 3167.21 3835.36 5087.54 3145.03 4277.46 5392.77 6147.85 4270.68 4690.39 31.68 66.72 46.08 96 60.24 123.84 49.2 106.56 267.12 305.52 219.12 240.24 63.96 113.88 172.38 243.75 371.28 462.15 292.89 375.18 200.46 255.06 184.08 214.5 94.32 155.52 275.04 361.44 586.08 696.24 467.28 567.36 570.96 637.92 388.08 424.8 214.63 659.13 466.09 1097.28 991.87 1797.05 807.72 1535.43 1765.3 2250.44 1391.92 1662.43 50.84 82.15 86.18 130.82 92.38 149.11 90.83 142.29 223.51 257.92 215.45 234.36 Annex 1 Water Quality Table used in the survey Annex 2. Detailed data source for River water pollution Data Source Cities Data Description 1. The weekly report of automatic water quality testing system Guigang City, Wuzhou Transferring from for main rivers of China City, Guangzhou City, Weekly Average to Zhongshan City, Nanning Monthly Average City, Guiyang City, Kunming City 2. Environmental Information system of the environmental protection bureau of Guangdong Province Shenzhen City, Gongduan Monthly Average City, Yunfu City, Zhaoqing City, Zhuhai City, Foshan City 3. Monthly report for the water quality of the main rivers in Guizhou province. Qiannan City, Qianxinan City, Guiyang City, Monthly Average 4. Monthly report for the water quality of the main rivers in Guangxi province. Baise City, Liuzhou City Monthly Average 5. Monthly environmental quality reportof the main rivers in Yunnan province. Qujing City, Yuxi City, Monthly Average Annex 3. Distribution of results of two-stage approach (Wang & He, 2011) WTP Mean Distribution of n. obs 727 Sample mean of : 75.99 Sample Std. Deviation of : 103.33 WTP Std. Variance Distribution of Sample mean of : 43.29 Sample Std. Deviation of : 72.65 Obs 727 Percentile 0 10 20 30 40 50 60 70 80 90 100 Percentile 0 10 20 30 40 50 60 70 80 90 100 Centile 0.1 6.1 11.2 16.0 21.7 34.4 55.5 85.6 129.5 129.5 999.7 Centile 0.3 1.1 2.3 5.6 8.2 12.1 23.2 482 72.6 108.9 567.9 [95% Conf. 0.1 5.9 11.0 15.2 20.7 29.2 55.5 78.2 106.3 175.0 999.7 [95% Conf. 0.3 0.5 1.8 4.7 6.9 10.0 24.7 37.5 61.5 96.3 567.9 Interval] 0.1 8.3 13.2 19.1 24.2 44.3 65.7 92.8 141.5 215.3 999.7 Interval] 0.3 1.4 3.6 6.4 9.1 14.1 30.7 52.1 80.0 127.4 567.9 Annex 4. Cross-table between realization probability and respondent’s location on the river (stage) MBDC 0 It has some possibility that It has some possibility that the the project can be realized on Cannot be realize project cannot be realized on time time 3.20% 47.60% 31.90% 1 5.50% 31.50% 46.60% 2 7.50% 39.10% 21.30% 3 18.20% 36.40% 27.30% 4 0.00% 60.00% 13.30% 5 0.00% 40.00% 34.30% 6 0.00% 45.70% 42.90% 7 5.00% 51.20% 24.80% 8 0.00% 40.00% 26.70% stage stage 0 It will be realized on time DC It has some possibility that It will be realized on It has some possibility that the the project can be realized on Cannot be realize time project cannot be realized on time time 2.00% 40.90% 33.60% 1 3.00% 36.40% 33.30% 2 1.10% 49.50% 23.40% 3 2.50% 30.00% 27.50% 4 6.70% 53.30% 26.70% 5 0.00% 39.00% 34.10% 6 0.00% 35.90% 48.70% 7 3.90% 28.10% 45.30% 8 0.00% 38.90% 44.40% Annex 5. Results of other three models Table A5.1 Estimation results with spatial factors, MBDC data, Definitely Yes model, Welsh and Poe (1998) Bid price rep_gov water_problem will_service quality_deg age education income_level Income significant higher than need male Can see the river Far from the river d_fish share2nd pop_density gdp_growth degree H1 -0.025 (34.88)*** -0.226 (2.50)** 0.038 (0.48) 0.165 (3.95)*** 0.233 (2.86)*** -0.001 (0.39) 0.011 (0.85) 0.051 (4.63)*** 0.300 (3.06)*** -0.042 (0.54) -0.080 (0.59) -0.100 (0.78) 0.121 (1.27) -0.001 (0.23) -0.027 (7.07)*** -0.013 (0.53) 0.184 (5.46)*** degree_upper H2 -0.025 (34.90)*** -0.241 (2.67)*** 0.117 (1.45) 0.129 (3.07)*** 0.240 (2.95)*** 0.001 (0.40) 0.009 (0.72) 0.046 (4.21)*** 0.326 (3.31)*** -0.043 (0.56) -0.067 (0.50) -0.103 (0.80) 0.094 (0.98) -0.016 (3.22)*** -0.015 (3.38)*** 0.023 (0.92) 0.193 (5.70)*** -0.174 (6.36)*** H3 -0.025 (34.89)*** -0.228 (2.53)** 0.109 (1.36) 0.133 (3.15)*** 0.199 (2.44)** 0.000 (0.07) 0.012 (0.89) 0.051 (4.69)*** 0.305 (3.11)*** -0.044 (0.57) -0.058 (0.43) -0.080 (0.63) 0.101 (1.06) -0.016 (3.12)*** -0.012 (2.63)*** -0.009 (0.38) 0.204 (6.02)*** -0.259 (5.69)*** degu_pop H4 -0.025 (34.91)** -0.231 (2.56)* 0.052 (0.65) 0.136 (3.23)** 0.215 (2.64)** -0.000 (0.09) 0.005 (0.37) 0.050 (4.58)** 0.337 (3.42)** -0.076 (0.97) -0.052 (0.39) -0.117 (0.91) 0.095 (0.99) -0.002 (0.44) -0.022 (5.55)** -0.042 (1.65) 0.177 (5.24)** Definitely Yes (727 obs.) H4 H4 -0.025 -0.026 (34.91)** (34.90)** -0.191 -0.241 (2.11)* (2.68)** 0.072 0.123 (0.90) (1.53) 0.148 0.124 (3.53)** (2.93)** 0.202 0.220 (2.48)* (2.71)** 0.002 0.001 (0.42) (0.29) 0.010 0.011 (0.76) (0.82) 0.051 0.050 (4.66)** (4.62)** 0.301 0.317 (3.07)** (3.22)** -0.044 -0.054 (0.57) (0.69) -0.003 -0.065 (0.02) (0.48) -0.056 -0.099 (0.43) (0.77) 0.139 0.103 (1.46) (1.07) 0.002 -0.018 (0.39) (3.73)** -0.013 -0.012 (2.86)** (2.81)** -0.008 0.004 (0.33) (0.17) 0.147 0.198 (4.28)** (5.86)** -0.138 (5.82)** degu_gdppc -0.075 (5.56)** Log likelihood LR Mean WTP KR CI Ratio -0.306 (0.58) -2184.30 27.21 [24.09 30.44] 0.23 0.087 (0.17) -2164.04 40.53 (0.000)*** 27.31 [24.54 30.19] 0.21 0.351 (0.66) -2168.07 32.46 (0.000)*** 27.31 [24.54 30.21] 0.21 0.518 (0.96) -2167.33 33.94 (0.000)*** 27.26 [25.24 30.39] 0.19 H5 -0.025 (34.91)** -0.206 (2.29)* 0.098 (1.22) 0.142 (3.39)** 0.191 (2.34)* 0.001 (0.25) 0.011 (0.85) 0.050 (4.54)** 0.306 (3.12)** -0.039 (0.50) -0.036 (0.27) -0.066 (0.51) 0.099 (1.04) -0.010 (2.13)* -0.008 (1.45) -0.006 (0.24) 0.190 (5.63)** H5 -0.025 (34.88)** -0.230 (2.55)* 0.113 (1.41) 0.129 (3.06)** 0.190 (2.33)* -0.000 (0.04) 0.013 (1.01) 0.055 (4.98)** 0.298 (3.04)** -0.052 (0.68) -0.062 (0.46) -0.083 (0.65) 0.115 (1.21) -0.017 (3.38)** -0.013 (2.70)** -0.022 (0.89) 0.209 (6.14)** -0.313 (6.08)** degu_gdpgwr Constant H5 -0.025 (34.90)** -0.234 (2.59)** 0.076 (0.95) 0.129 (3.07)** 0.214 (2.64)** -0.001 (0.17) 0.005 (0.42) 0.051 (4.63)** 0.330 (3.35)** -0.067 (0.87) -0.069 (0.51) -0.111 (0.86) 0.078 (0.81) -0.010 (2.24)* -0.018 (4.25)** -0.051 (2.00)* 0.211 (6.19)** -0.298 (0.57) -2168.81 30.99 (0.000)*** 27.26 [25.23 30.4] 0.19 -0.180 (5.70)** -0.172 (7.01)** -0.172 (7.01)** -2159.7 49.2 (0.000)*** 27.31 [25.29 30.4] 0.19 0.909 (1.62) -2165.79 37.03 (0.000)*** 27.28 [25.26 30.4] 0.19 -0.001 (0.00) -2168.02 29.55 (0.000)*** 27.3 [25.25 30.41] 0.19 -0.223 (5.84)** 0.579 (1.06) -2167.21 34.18 (0.006)*** 27.31 [25.27 30.42] 0.19 Table A5.2 Estimation results with spatial factors, MBDC2 data, Welsh and Poe (1998) Not sure model. Bid price rep_gov water_problem will_service quality_deg age education income_level Income significant higher than need male Can see the river Far from the river d_fish share2nd pop_density gdp_growth degree H1 -0.009 (36.11)*** -0.126 (1.41) 0.067 (0.86) 0.167 (4.04)*** 0.222 (2.76)*** -0.003 (0.73) -0.003 (0.27) 0.036 (3.28)*** 0.291 (2.99)*** -0.054 (0.70) -0.325 (2.43)** -0.395 (3.11)*** 0.057 (0.60) -0.011 (2.71)*** -0.009 (2.30)** 0.117 (4.74)*** 0.049 (1.49) degree_upper H2 -0.009 (36.11)*** -0.128 (1.44) 0.090 (1.12) 0.156 (3.74)*** 0.223 (2.77)*** -0.002 (0.50) -0.004 (0.31) 0.034 (3.12)*** 0.297 (3.04)*** -0.054 (0.70) -0.321 (2.41)** -0.396 (3.12)*** 0.048 (0.51) -0.016 (3.24)*** -0.005 (1.17) 0.127 (5.03)*** 0.051 (1.53) -0.048 (1.81)* H3 -0.009 (36.12)*** -0.125 (1.39) 0.103 (1.29) 0.150 (3.60)*** 0.205 (2.54)** -0.002 (0.49) -0.003 (0.25) 0.035 (3.27)*** 0.293 (3.00)*** -0.055 (0.72) -0.315 (2.36)** -0.387 (3.05)*** 0.046 (0.48) -0.019 (3.77)*** -0.001 (0.24) 0.120 (4.85)*** 0.058 (1.75)* -0.127 (2.84)*** degu_pop H4 -0.009 (36.11)** -0.126 (1.41) 0.070 (0.89) 0.161 (3.85)** 0.218 (2.71)** -0.002 (0.67) -0.005 (0.36) 0.035 (3.25)** 0.298 (3.05)** -0.061 (0.79) -0.319 (2.39)* -0.398 (3.13)** 0.051 (0.53) -0.012 (2.75)** -0.008 (1.93) 0.111 (4.44)** 0.047 (1.43) Not Sure (727 obs) H4 -0.009 (36.12)** -0.107 (1.19) 0.084 (1.06) 0.158 (3.81)** 0.206 (2.55)* -0.001 (0.33) -0.004 (0.32) 0.035 (3.26)** 0.290 (2.97)** -0.055 (0.72) -0.288 (2.15)* -0.375 (2.95)** 0.064 (0.68) -0.010 (2.41)* -0.002 (0.36) 0.121 (4.88)** 0.030 (0.90) -0.028 (1.19) degu_gdppc Log likelihood LR Mean WTP KR CI Ratio H5 -0.009 (36.11)** -0.127 (1.42) 0.079 (1.00) 0.155 (3.71)** 0.216 (2.68)** -0.002 (0.66) -0.005 (0.40) 0.035 (3.25)** 0.299 (3.06)** -0.062 (0.81) -0.321 (2.40)* -0.398 (3.14)** 0.043 (0.45) -0.014 (3.18)** -0.006 (1.36) 0.106 (4.18)** 0.056 (1.70) -0.036 (2.76)** -0.749 (1.44) -2312.00 92.56 [84.07 101.28] 0.19 -0.643 (1.23) -2310.37 3.26 (0.0710)* 92.56 [84.95 100.55] 0.17 -0.441 (0.83) -2307.98 8.04 (0.0046)*** 92.57 [84.98 100.53] 0.17 -0.586 (1.09) -2311.29 1.42 (0.233) 92.56 [86.89 101.18] 0.15 H5 -0.009 (36.12)** -0.115 (1.29) 0.094 (1.18) 0.156 (3.76)** 0.203 (2.51)* -0.002 (0.43) -0.004 (0.27) 0.035 (3.20)** 0.293 (3.00)** -0.053 (0.69) -0.306 (2.29)* -0.381 (3.00)** 0.046 (0.49) -0.015 (3.40)** 0.000 (0.03) 0.121 (4.90)** 0.051 (1.54) H5 -0.009 (36.11)** -0.126 (1.41) 0.117 (1.47) 0.143 (3.41)** 0.194 (2.40)* -0.002 (0.49) -0.002 (0.18) 0.038 (3.47)** 0.289 (2.96)** -0.062 (0.80) -0.315 (2.36)* -0.388 (3.05)** 0.051 (0.54) -0.022 (4.38)** 0.001 (0.30) 0.113 (4.58)** 0.064 (1.92) -0.095 (1.89) degu_gdpgwr Constant H4 -0.009 (36.11)** -0.130 (1.45) 0.107 (1.34) 0.147 (3.51)** 0.214 (2.66)** -0.002 (0.41) -0.004 (0.30) 0.035 (3.22)** 0.296 (3.04)** -0.059 (0.77) -0.319 (2.39)* -0.397 (3.12)** 0.046 (0.49) -0.019 (3.96)** -0.002 (0.37) 0.126 (5.08)** 0.054 (1.63) -0.833 (1.60) -2308.18 7.64 (0.004) *** 92.57 [86.92 101.15] 0.15 -0.078 (2.53)* -0.078 (3.24)** -0.409 (0.77) -2306.75 10.5 (0.001)*** 92.57 [86.9 101.13] 0.15 -0.386 (0.70) -2310.21 3.59 (0.058)* 92.56 [86.89 101.17] 0.15 -0.658 (1.27) -2308.81 6.39 (0.001) *** 92.58 [86.9 101.15] 0.15 -0.146 (3.89)** -0.190 (0.35) -2304.43 15.13 (0.006)*** 92.57 [86.93 101.1] 0.15 Table A5.3 Estimation results with spatial factors, DC2 data, Single bound, simple probit model Bid price rep_gov water_problem will_service quality_deg age education income_level Income significant higher than need male Can see the river Far from the river d_fish share2nd pop_density gdp_growth degree H1 -0.005 (13.01)*** -0.265 (2.37)** 0.087 (0.84) 0.352 (6.69)*** 0.370 (3.60)*** -0.002 (0.40) 0.000 (0.02) 0.055 (4.09)*** 0.187 (1.49) 0.031 (0.32) -0.079 (0.45) -0.020 (0.12) 0.174 (1.47) -0.003 (0.58) -0.002 (0.38) -0.017 (0.54) 0.137 (3.45)*** degree_upper H2 -0.005 (13.01)*** -0.266 (2.38)** 0.088 (0.85) 0.350 (6.62)*** 0.372 (3.60)*** -0.002 (0.40) 0.000 (0.02) 0.055 (4.09)*** 0.188 (1.50) 0.032 (0.33) -0.076 (0.43) -0.015 (0.09) 0.173 (1.46) -0.004 (0.60) -0.002 (0.28) -0.015 (0.49) 0.138 (3.45)*** -0.005 (0.15) H3 -0.005 (13.02)*** -0.271 (2.42)** 0.095 (0.92) 0.344 (6.48)*** 0.369 (3.59)*** -0.002 (0.39) 0.001 (0.08) 0.056 (4.13)*** 0.196 (1.56) 0.032 (0.33) -0.063 (0.36) 0.014 (0.08) 0.163 (1.37) -0.006 (0.91) 0.001 (0.16) -0.015 (0.50) 0.142 (3.52)*** -0.052 (0.87) degu_pop H4 -0.005 (13.00)** -0.262 (2.32)* 0.087 (0.84) 0.354 (6.67)** 0.369 (3.59)** -0.002 (0.38) 0.000 (0.00) 0.055 (4.08)** 0.185 (1.48) 0.031 (0.32) -0.083 (0.47) -0.026 (0.16) 0.177 (1.49) -0.003 (0.57) -0.002 (0.43) -0.016 (0.50) 0.138 (3.46)** Single Bound (910 obs.) H4 -0.005 (13.01)** -0.269 (2.40)* 0.091 (0.88) 0.343 (6.47)** 0.381 (3.69)** -0.002 (0.37) 0.002 (0.11) 0.055 (4.08)** 0.197 (1.57) 0.029 (0.30) -0.056 (0.32) 0.014 (0.08) 0.168 (1.41) -0.003 (0.47) 0.002 (0.30) -0.015 (0.49) 0.132 (3.27)** 0.009 (0.33) degu_gdppc Log likelihood LR Mean WTP KR CI Ratio H5 -0.005 (13.02)** -0.273 (2.42)* 0.089 (0.86) 0.346 (6.51)** 0.369 (3.59)** -0.002 (0.42) 0.001 (0.07) 0.055 (4.11)** 0.191 (1.52) 0.030 (0.31) -0.069 (0.39) -0.004 (0.02) 0.167 (1.40) -0.004 (0.73) -0.001 (0.17) -0.020 (0.63) 0.141 (3.49)** -0.018 (1.21) -1.130 (1.73)* -457.41 134.23 [115.55 154.06] 0.29 -1.125 (1.72)* -457.40 0.02 (0.8793) 134.22 [117.46 153.67] 0.27 -1.043 (1.58) -457.03 0.76 (0.3827) 135.01 [117.53 153.61] 0.27 -1.170 (1.76) -457.36 0.11 (0.741) 134.23 [120.96 154.98] 0.25 H5 -0.005 (13.01)** -0.270 (2.41)* 0.091 (0.88) 0.345 (6.48)** 0.371 (3.61)** -0.002 (0.38) 0.001 (0.08) 0.055 (4.12)** 0.194 (1.55) 0.030 (0.31) -0.064 (0.36) 0.008 (0.05) 0.165 (1.38) -0.004 (0.76) 0.001 (0.17) -0.015 (0.49) 0.139 (3.48)** H5 -0.005 (13.01)** -0.272 (2.42)* 0.096 (0.93) 0.343 (6.46)** 0.364 (3.54)** -0.002 (0.40) 0.002 (0.11) 0.056 (4.15)** 0.199 (1.58) 0.033 (0.34) -0.061 (0.35) 0.021 (0.12) 0.161 (1.35) -0.006 (1.00) 0.001 (0.24) -0.018 (0.57) 0.143 (3.54)** -0.038 (0.60) degu_gdpgwr Constant H4 -0.005 (13.01)** -0.268 (2.39)* 0.090 (0.87) 0.349 (6.58)** 0.372 (3.62)** -0.002 (0.40) 0.000 (0.03) 0.055 (4.10)** 0.190 (1.52) 0.033 (0.34) -0.072 (0.41) -0.007 (0.04) 0.171 (1.44) -0.004 (0.69) -0.001 (0.17) -0.015 (0.49) 0.138 (3.46)** -1.173 (1.79) -456.68 1.47 (0.225) 134.2 [120.91 154.78] 0.25 -0.025 (0.75) -0.012 (0.38) -0.172 (7.01)** -457.34 0.15 (0.702) 134.22 [120.93 154.83] 0.25 -1.025 (1.51) -457.24 0.36 (0.551) 134.29 [121.14 155.04] 0.25 -1.109 (1.70) -457.13 0.57 (0.927) 134.22 [120.94 154.79] 0.25 -0.052 (1.03) -0.987 (1.48) -456.88 1.06 (0.302) 134.3 [121.1 154.96] 0.25 Annex 6. Detailed of the model estimation results related to the two robustness check Tables A6.1 Robustness check: substitute variable: distance weighted aggregate Industrial Output Bid price rep_gov water_problem will_service quality_deg age education income_level Income significant higher than need male Can see the river Far from the river d_fish Degree share2nd pop_density gdp_growth H1 -0.025 (34.88)*** -0.226 (2.50)** 0.038 (0.48) 0.165 (3.95)*** 0.233 (2.86)*** -0.001 (0.39) 0.011 (0.85) 0.051 (4.63)*** 0.300 (3.06)*** -0.042 (0.54) -0.080 (0.59) -0.100 (0.78) 0.121 (1.27) 0.184 (5.46)*** -0.001 (0.23) -0.027 (7.07)*** -0.013 (0.53) Total Output H2 -0.025 (34.87)*** -0.238 (2.64)*** 0.087 (1.08) 0.130 (3.07)*** 0.225 (2.77)*** -0.002 (0.43) 0.012 (0.90) 0.056 (5.11)*** 0.307 (3.12)*** -0.052 (0.67) -0.068 (0.51) -0.077 (0.60) 0.151 (1.57) 0.194 (5.75)*** -0.008 (1.79)* -0.023 (5.73)*** -0.045 (1.76)* -3.3510-7 (4.60)*** H3 -0.025 (34.86)*** -0.226 (2.51)** 0.079 (0.99) 0.139 (3.27)*** 0.205 (2.51)** -0.002 (0.41) 0.014 (1.08) 0.058 (5.25)*** 0.285 (2.91)*** -0.056 (0.73) -0.067 (0.50) -0.086 (0.67) 0.165 (1.71)* 0.198 (5.83)*** -0.011 (2.12)** -0.024 (5.92)*** -0.035 (1.39) -0.000017 (3.77)*** output_pop H4 -0.025 (34.91)** -0.207 (2.30)* 0.110 (1.37) 0.136 (3.24)** 0.236 (2.90)** 0.001 (0.16) 0.009 (0.70) 0.050 (4.55)** 0.288 (2.93)** -0.042 (0.55) -0.062 (0.46) -0.099 (0.78) 0.096 (1.01) 0.226 (6.55)** -0.012 (2.55)* -0.002 (0.30) -0.029 (1.17) -0.001 (5.89)** output _gdppc Def Yes H4 -0.025 (34.91)** -0.183 (2.02)* 0.137 (1.69) 0.136 (3.23)** 0.214 (2.63)** -0.000 (0.07) 0.012 (0.95) 0.051 (4.63)** 0.278 (2.83)** -0.032 (0.42) -0.061 (0.46) -0.052 (0.40) 0.077 (0.80) 0.199 (5.89)** -0.001 (0.32) -0.001 (0.25) 0.024 (0.96) -0.000 (6.01)** output _gdpgwr Constant Log likelihood LR Mean WTP KR CI Ratio -0.306 (0.58) -2184.30 27.21 [24.09 30.44] 0.23 0.586 (1.05) -2173.72 21.18 (0.000)*** 27.27 [24.47 30.21] 0.21 0.439 (0.79) -2177.21 14.18 (0.0002)*** 27.26 [24.44 30.21] 0.21 0.200 (0.38) -2166.93 34.75 (0.000)*** 27.28 [25.28 30.42] 0.19 -1.025 (1.91) -2166.24 36.13 (0.000)*** 27.28 [25.27 30.42] 0.19 H4 -0.025 (34.89)** -0.209 (2.32)* 0.133 (1.63) 0.132 (3.12)** 0.203 (2.49)* -0.001 (0.27) 0.014 (1.12) 0.054 (4.97)** 0.282 (2.87)** -0.045 (0.58) -0.080 (0.60) -0.071 (0.55) 0.099 (1.03) 0.217 (6.34)** -0.011 (2.35)* -0.006 (1.22) 0.000 (0.01) H5 -0.025 (34.88)** -0.220 (2.44)* 0.101 (1.26) 0.133 (3.15)** 0.212 (2.61)** -0.001 (0.24) 0.012 (0.97) 0.056 (5.11)** 0.283 (2.88)** -0.054 (0.69) -0.073 (0.54) -0.096 (0.75) 0.137 (1.43) 0.223 (6.44)** -0.015 (3.00)** -0.014 (2.88)** -0.036 (1.43) -0.000 (5.00)** -0.001 (5.73)** -0.216 (0.41) -2167.87 32.87 (0.000)*** 27.29 [25.31 30.45] 0.19 0.565 (1.02) -2171.8 25 (0.000)*** 27.28 [25.3 30.44] 0.19 H5 -0.025 (34.88)** -0.214 (2.37)* 0.121 (1.49) 0.130 (3.08)** 0.199 (2.45)* -0.001 (0.37) 0.015 (1.14) 0.057 (5.16)** 0.279 (2.84)** -0.050 (0.65) -0.078 (0.58) -0.075 (0.58) 0.123 (1.29) 0.214 (6.24)** -0.012 (2.52)* -0.013 (2.73)** -0.007 (0.30) -0.001 (5.17)** 0.017 (0.03) -2170.92 26.77 (0.000)*** 27.29 [25.31 30.45] 0.19 H5 -0.025 (34.87)** -0.218 (2.42)* 0.104 (1.29) 0.134 (3.18)** 0.193 (2.36)* -0.001 (0.36) 0.015 (1.18) 0.058 (5.26)** 0.278 (2.83)** -0.055 (0.71) -0.072 (0.53) -0.082 (0.64) 0.145 (1.51) 0.209 (6.13)** -0.013 (2.62)** -0.016 (3.60)** -0.022 (0.90) -0.000 (4.65)** 0.276 (0.51) -2173.49 21.62 (0.000)*** 27.28 [25.3 30.45] 0.19 Tables A6.2 Robustness check: substitute variable: distance weighted aggregate Industrial Output(continue) Bid price rep_gov water_problem will_service quality_deg age education income_level Income significant higher than need male Can see the river Far from the river d_fish Degree share2nd pop_density gdp_growth H1 -0.016 (36.10)*** -0.310 (3.45)*** 0.027 (0.34) 0.169 (4.09)*** 0.305 (3.77)*** -0.003 (0.95) 0.002 (0.12) 0.039 (3.62)*** 0.371 (3.79)*** 0.026 (0.34) -0.163 (1.22) -0.191 (1.51) 0.180 (1.89)* 0.137 (4.11)*** -0.005 (1.21) -0.022 (5.59)*** 0.057 (2.31)** Total Output H2 -0.017 (36.08)*** -0.323 (3.58)*** 0.072 (0.90) 0.138 (3.26)*** 0.299 (3.69)*** -0.004 (0.98) 0.002 (0.16) 0.044 (4.05)*** 0.379 (3.87)*** 0.017 (0.22) -0.151 (1.13) -0.171 (1.35) 0.208 (2.17)** 0.146 (4.39)*** -0.012 (2.59)*** -0.017 (4.36)*** 0.029 (1.13) -3.0710-7 (4.25)*** H3 -0.017 (36.09)*** -0.312 (3.47)*** 0.075 (0.94) 0.139 (3.31)*** 0.274 (3.38)*** -0.004 (0.98) 0.005 (0.38) 0.048 (4.37)*** 0.356 (3.63)*** 0.009 (0.12) -0.147 (1.10) -0.177 (1.39) 0.231 (2.41)** 0.153 (4.57)*** -0.016 (3.29)*** -0.017 (4.32)*** 0.032 (1.28) -0.00020 (4.41)*** output_pop H4 -0.017 (36.09)** -0.297 (3.29)** 0.084 (1.05) 0.146 (3.50)** 0.307 (3.79)** -0.002 (0.51) -0.000 (0.00) 0.038 (3.52)** 0.362 (3.69)** 0.026 (0.33) -0.149 (1.12) -0.193 (1.52) 0.161 (1.69) 0.169 (4.98)** -0.014 (2.96)** -0.001 (0.19) 0.046 (1.86) -0.001 (4.67)** output _gdppc Prob Yes H4 -0.017 (36.09)** -0.270 (2.99)** 0.125 (1.54) 0.141 (3.37)** 0.287 (3.54)** -0.002 (0.64) 0.003 (0.21) 0.039 (3.58)** 0.351 (3.58)** 0.036 (0.46) -0.147 (1.10) -0.148 (1.17) 0.138 (1.45) 0.152 (4.55)** -0.006 (1.32) 0.004 (0.75) 0.096 (3.77)** -0.000 (5.94)** output _gdpgwr Constant Log likelihood LR Mean WTP KR CI Ratio -0.557 (1.07) -2202.27 52.68 [48.00 57.48] 0.18 0.239 (0.43) -2193.23 18.08 (0.0002)*** 52.69 [48.56 57.02] 0.16 0.292 (0.53) -2192.54 19.46 (0.000)*** 52.69 [48.56 57.02] 0.16 -0.178 (0.34) -2191.36 21.83 (0.000)*** 52.69 [49.63 57.39] 0.15 -1.288 (2.41)* -2184.59 35.36 (0.000)*** 52.71 [49.69 57.37] 0.15 H4 -0.017 (36.08)** -0.296 (3.28)** 0.125 (1.54) 0.135 (3.23)** 0.275 (3.39)** -0.003 (0.83) 0.005 (0.39) 0.043 (3.94)** 0.355 (3.61)** 0.023 (0.30) -0.165 (1.23) -0.165 (1.30) 0.159 (1.66) 0.171 (5.06)** -0.015 (3.34)** 0.000 (0.04) 0.073 (2.94)** H5 -0.017 (36.09)** -0.307 (3.41)** 0.088 (1.09) 0.139 (3.30)** 0.287 (3.54)** -0.003 (0.81) 0.003 (0.23) 0.044 (4.07)** 0.356 (3.63)** 0.015 (0.19) -0.156 (1.17) -0.189 (1.49) 0.196 (2.05)* 0.174 (5.09)** -0.019 (3.70)** -0.008 (1.74) 0.037 (1.47) -0.000 (4.82)** -0.001 (5.92)** -0.491 (0.94) -2184.75 35.04 (0.000)*** 52.71 [49.68 57.37] 0.15 0.253 (0.46) -2190.66 23.22 (0.000)*** 52.7 [49.63 57.38] 0.15 H5 -0.017 (36.09)** -0.300 (3.33)** 0.116 (1.44) 0.132 (3.15)** 0.271 (3.33)** -0.003 (0.94) 0.006 (0.43) 0.046 (4.18)** 0.351 (3.58)** 0.017 (0.22) -0.162 (1.21) -0.168 (1.32) 0.183 (1.92) 0.169 (4.99)** -0.017 (3.57)** -0.006 (1.24) 0.065 (2.64)** -0.001 (5.56)** -0.235 (0.45) -2190.66 30.99 (0.000)*** 52.71 [49.66 57.38] 0.15 H5 -0.017 (36.09)** -0.304 (3.38)** 0.103 (1.28) 0.135 (3.22)** 0.261 (3.21)** -0.003 (0.92) 0.006 (0.49) 0.048 (4.36)** 0.349 (3.56)** 0.011 (0.14) -0.154 (1.15) -0.174 (1.37) 0.208 (2.18)* 0.166 (4.92)** -0.019 (3.81)** -0.009 (1.95) 0.048 (1.96) -0.000 (5.33)** 0.083 (0.16) -2188.04 28.46 (0.000)*** 52.7 [49.65 57.37] 0.15 Tables A6.3 Robustness check: substitute variable: distance weighted aggregate Industrial Output(continue) Bid price rep_gov water_problem will_service quality_deg age education income_level Income significant higher than need male Can see the river Far from the river d_fish Degree share2nd pop_density gdp_growth H1 -0.009 (36.11)*** -0.126 (1.41) 0.067 (0.86) 0.167 (4.04)*** 0.222 (2.76)*** -0.003 (0.73) -0.003 (0.27) 0.036 (3.28)*** 0.291 (2.99)*** -0.054 (0.70) -0.325 (2.43)** -0.395 (3.11)*** 0.057 (0.60) 0.049 (1.49) -0.011 (2.71)*** -0.009 (2.30)** 0.117 (4.74)*** Total Output H2 -0.009 (36.10)*** -0.134 (1.49) 0.105 (1.32) 0.140 (3.34)*** 0.216 (2.69)*** -0.003 (0.74) -0.003 (0.24) 0.039 (3.62)*** 0.297 (3.04)*** -0.062 (0.81) -0.317 (2.37)** -0.380 (2.99)*** 0.078 (0.82) 0.056 (1.69)* -0.017 (3.75)*** -0.005 (1.29) 0.094 (3.69)*** -2.5410-7 (3.53)*** H3 -0.009 (36.10)*** -0.125 (1.40) 0.125 (1.57) 0.132 (3.15)*** 0.186 (2.30)** -0.003 (0.75) 0.000 (0.03) 0.046 (4.17)*** 0.274 (2.80)*** -0.075 (0.98) -0.312 (2.33)** -0.384 (3.02)*** 0.114 (1.19) 0.067 (2.01)** -0.024 (4.96)*** -0.003 (0.87) 0.089 (3.55)*** -0.0000231 (5.14)*** output_pop H4 -0.009 (36.11)** -0.116 (1.30) 0.097 (1.21) 0.154 (3.71)** 0.222 (2.76)** -0.002 (0.49) -0.004 (0.34) 0.035 (3.21)** 0.285 (2.92)** -0.055 (0.71) -0.318 (2.38)* -0.396 (3.12)** 0.045 (0.48) 0.065 (1.93) -0.016 (3.45)** 0.002 (0.33) 0.111 (4.50)** -0.000 (2.44)* output _gdppc Not Sure H4 -0.009 (36.12)** -0.094 (1.05) 0.134 (1.66) 0.147 (3.53)** 0.208 (2.58)** -0.002 (0.51) -0.003 (0.22) 0.035 (3.23)** 0.275 (2.82)** -0.048 (0.63) -0.315 (2.36)* -0.367 (2.89)** 0.026 (0.27) 0.057 (1.74) -0.012 (2.79)** 0.009 (1.54) 0.144 (5.63)** -0.000 (4.05)** Log likelihood LR Mean WTP KR CI Ratio H5 -0.009 (36.11)** -0.119 (1.34) 0.120 (1.51) 0.140 (3.35)** 0.205 (2.54)* -0.002 (0.59) -0.002 (0.19) 0.040 (3.65)** 0.277 (2.84)** -0.065 (0.85) -0.322 (2.41)* -0.397 (3.12)** 0.068 (0.72) 0.080 (2.37)* -0.023 (4.59)** 0.003 (0.63) 0.100 (4.01)** -0.000 (4.19)** -0.749 (1.44) -2312.00 -0.092 (0.17) -2305.76 12.48 (0.0004)*** 0.235 (0.42) -2298.76 26.48 (0.000)*** -0.552 (1.05) -2309.03 5.94 (0.01)** -1.240 (2.33)* -2303.8 16.4 (0.000)*** -0.000 (4.75)** -0.698 (1.34) -2300.72 22.56 (0.000)*** 92.56 [84.07 101.28] 0.19 92.57 [85.02 100.50] 0.17 92.57 [85.09 100.42] 0.17 92.57 [86.89 0.15 101.19] 92.58 [86.96 101.15] 0.15 92.58 [86.98 101.12] 0.15 output _gdpgwr Constant H4 -0.009 (36.11)** -0.109 (1.22) 0.146 (1.81) 0.139 (3.34)** 0.196 (2.43)* -0.002 (0.62) -0.001 (0.07) 0.038 (3.52)** 0.275 (2.82)** -0.057 (0.75) -0.329 (2.46)* -0.378 (2.97)** 0.037 (0.39) 0.074 (2.22)* -0.020 (4.29)** 0.009 (1.67) 0.130 (5.25)** H5 -0.009 (36.11)** -0.111 (1.24) 0.151 (1.88) 0.133 (3.16)** 0.189 (2.34)* -0.003 (0.70) 0.000 (0.00) 0.041 (3.78)** 0.271 (2.77)** -0.063 (0.83) -0.328 (2.46)* -0.378 (2.97)** 0.057 (0.60) 0.077 (2.29)* -0.022 (4.74)** 0.006 (1.26) 0.125 (5.07)** -0.001 (5.17)** H5 -0.009 (36.11)** -0.115 (1.29) 0.146 (1.82) 0.132 (3.16)** 0.176 (2.18)* -0.002 (0.69) 0.001 (0.09) 0.044 (4.03)** 0.267 (2.73)** -0.071 (0.93) -0.321 (2.40)* -0.383 (3.01)** 0.082 (0.87) 0.077 (2.31)* -0.026 (5.15)** 0.004 (1.00) 0.109 (4.43)** -0.051 (0.09) -2303.22 17.55 (0.000)*** -0.455 (0.87) -2298.61 26.77 (0.000)*** -0.000 (5.45)** -0.102 (0.19) -2297.14 29.72 (0.000)*** 92.57 [86.94 101.12] 0.15 92.58 [86.99 101.09] 0.15 92.58 [87 101.07] 0.15 Tables A6.4 Robustness check: substitute variable: distance weighted aggregate Industrial Output(continue) Bid price rep_gov water_problem will_service quality_deg age education income_level Income significant higher than need male Can see the river Far from the river d_fish Degree share2nd pop_density gdp_growth H1 -0.011 (38.13)*** -18.436 (2.19)** 7.080 (0.95) 15.093 (3.87)*** 20.245 (2.67)*** -0.271 (0.79) -0.554 (0.46) 4.019 (3.96)*** 27.176 (2.96)*** -5.829 (0.81) -25.250 (2.02)** -28.295 (2.38)** 10.770 (1.20) 5.134 (1.65)* -0.917 (2.29)** -1.011 (2.83)*** 9.605 (4.16)*** Total Output H2 -0.011 (38.13)*** -18.993 (2.28)** 10.728 (1.44) 12.360 (3.14)*** 19.431 (2.59)*** -0.275 (0.81) -0.521 (0.43) 4.373 (4.32)*** 27.382 (3.01)*** -6.605 (0.92) -24.270 (1.95)* -26.521 (2.25)** 12.769 (1.43) 5.708 (1.85)* -1.433 (3.40)*** -0.646 (1.76)* 7.284 (3.07)*** -0.000025 (3.69)*** H3 -0.011 (38.13)*** -18.096 (2.19)** 12.229 (1.66)* 11.653 (3.00)*** 16.507 (2.21)** -0.275 (0.82) -0.212 (0.18) 4.911 (4.84)*** 25.036 (2.77)*** -7.636 (1.07) -23.611 (1.92)* -26.661 (2.28)** 15.865 (1.79)* 6.595 (2.14)** -2.079 (4.57)*** -0.510 (1.40) 6.921 (2.97)*** -0.002 (5.09)*** output_pop H4 -0.011 (38.13)** -17.408 (2.07)* 10.016 (1.33) 13.806 (3.53)** 20.065 (2.66)** -0.187 (0.55) -0.643 (0.53) 3.930 (3.88)** 26.356 (2.88)** -5.890 (0.82) -24.500 (1.96)* -28.230 (2.38)* 9.667 (1.08) 6.623 (2.10)* -1.342 (3.10)** 0.026 (0.05) 9.022 (3.90)** -0.041 (2.52)* output _gdppc Wang and He H4 -0.011 (38.13)** -14.975 (1.79) 14.097 (1.88) 12.773 (3.29)** 18.140 (2.42)* -0.204 (0.60) -0.450 (0.38) 3.977 (3.97)** 24.972 (2.76)** -5.283 (0.74) -24.055 (1.95) -24.743 (2.10)* 7.806 (0.88) 5.807 (1.89) -0.937 (2.37)* 0.700 (1.34) 12.381 (5.24)** -0.022 (4.44)** output _gdpgwr Constant Log likelihood LR Mean WTP KR CI Ratio -62.418 (1.27) -4344.03 75.99 [68.89 83.48] 0.19 2.316 (0.04) -4337.28 13.51 (0.0002)*** 75.99 [68.58 82.91] 0.18 28.273 (0.55) -4331.31 25.45 (0.000)*** 75.99 [68.63 82.86] 0.17 -42.992 (0.87) -4340.87 6.32 (0.01)** 75.99 [71.14 83.44] 0.16 -112.928 (2.27)* -4334.29 19.48 (0.000)*** 75.99 [71.19 83.37] 0.16 H4 -0.011 (38.13)** -16.569 (2.00)* 14.470 (1.93) 12.276 (3.16)** 17.406 (2.33)* -0.230 (0.68) -0.314 (0.26) 4.206 (4.20)** 25.093 (2.78)** -6.109 (0.86) -25.168 (2.04)* -26.076 (2.22)* 8.868 (1.00) 7.346 (2.37)* -1.660 (3.92)** 0.642 (1.30) 10.666 (4.67)** H5 -0.011 (38.13)** -17.602 (2.11)* 12.009 (1.61) 12.437 (3.19)** 18.314 (2.44)* -0.223 (0.66) -0.462 (0.39) 4.370 (4.34)** 25.434 (2.80)** -6.783 (0.95) -24.642 (1.99)* -27.986 (2.38)* 11.760 (1.33) 7.887 (2.50)* -2.011 (4.24)** 0.083 (0.19) 7.931 (3.42)** -0.025 (4.18)** -0.040 (4.80)** -56.131 (1.16) -4332.7 22.65 (0.000)*** 75.99 [71.2 83.36] 0.16 2.938 (0.06) -4335.41 17.23 (0.000)*** 75.99 [71.18 83.38] 0.16 H5 -0.011 (38.13)** -16.923 (2.04)* 14.480 (1.94) 11.807 (3.04)** 17.114 (2.29)* -0.247 (0.73) -0.276 (0.23) 4.407 (4.40)** 24.789 (2.74)** -6.570 (0.92) -25.101 (2.04)* -26.431 (2.26)* 10.424 (1.18) 7.647 (2.46)* -1.916 (4.33)** 0.368 (0.82) 10.052 (4.42)** -0.118 (4.97)** -32.159 (0.66) -4331.89 24.29 (0.000)*** 75.99 [71.2 83.35] 0.16 H5 -0.011 (38.13)** -17.113 (2.07)* 14.212 (1.92) 11.624 (3.00)** 15.555 (2.08)* -0.251 (0.75) -0.133 (0.11) 4.732 (4.71)** 24.340 (2.70)** -7.294 (1.03) -24.316 (1.98)* -26.468 (2.27)* 13.003 (1.48) 7.531 (2.44)* -2.182 (4.77)** 0.213 (0.51) 8.699 (3.83)** -0.016 (5.41)** -2.057 (0.04) -4329.68 28.7 (0.000)*** 75.99 [71.22 83.33] 0.16 Tables A6.5 Robustness check: substitute variable: distance weighted aggregate Industrial Output (continue) Bid price rep_gov water_problem will_service quality_deg age education income_level Income significant higher than need male Can see the river Far from the river d_fish Degree share2nd pop_density gdp_growth H1 -0.005 (13.01)*** -0.265 (2.37)** 0.087 (0.84) 0.352 (6.69)*** 0.370 (3.60)*** -0.002 (0.40) 0.000 (0.02) 0.055 (4.09)*** 0.187 (1.49) 0.031 (0.32) -0.079 (0.45) -0.020 (0.12) 0.174 (1.47) 0.137 (3.45)*** -0.003 (0.58) -0.002 (0.38) -0.017 (0.54) Total Output H2 -0.005 (13.02)*** -0.280 (2.50)** 0.098 (0.94) 0.338 (6.37)*** 0.354 (3.43)*** -0.002 (0.44) 0.004 (0.27) 0.056 (4.14)*** 0.206 (1.63) 0.029 (0.30) -0.052 (0.29) 0.034 (0.20) 0.160 (1.35) 0.141 (3.51)*** -0.006 (0.97) 0.000 (0.04) -0.033 (1.03) -1.7210-7 (1.90)* H3 -0.005 (13.00)*** -0.268 (2.38)** 0.109 (1.05) 0.338 (6.39)*** 0.329 (3.16)*** -0.002 (0.41) 0.005 (0.36) 0.058 (4.21)*** 0.219 (1.73)* 0.028 (0.29) -0.045 (0.25) 0.064 (0.38) 0.157 (1.32) 0.154 (3.77)*** -0.011 (1.68)* 0.001 (0.21) -0.032 (1.01) -0.000015 (2.47)** output_pop H4 -0.005 (13.01)** -0.265 (2.35)* 0.086 (0.83) 0.352 (6.63)** 0.370 (3.60)** -0.002 (0.40) 0.000 (0.02) 0.055 (4.09)** 0.186 (1.47) 0.031 (0.32) -0.080 (0.45) -0.022 (0.13) 0.175 (1.46) 0.137 (3.35)** -0.003 (0.53) -0.002 (0.31) -0.016 (0.53) 0.000 (0.06) output _gdppc Single Bound H4 -0.005 (13.01)** -0.261 (2.33)* 0.076 (0.73) 0.358 (6.75)** 0.358 (3.46)** -0.002 (0.40) -0.000 (0.03) 0.055 (4.10)** 0.176 (1.40) 0.031 (0.32) -0.088 (0.50) -0.050 (0.30) 0.189 (1.58) 0.135 (3.37)** -0.004 (0.63) -0.007 (0.93) -0.023 (0.74) 0.000 (0.90) Log likelihood LR Mean WTP KR CI Ratio H5 -0.005 (13.02)** -0.274 (2.44)* 0.100 (0.97) 0.343 (6.47)** 0.358 (3.47)** -0.002 (0.38) 0.001 (0.09) 0.056 (4.14)** 0.205 (1.63) 0.033 (0.34) -0.058 (0.33) 0.027 (0.16) 0.158 (1.32) 0.152 (3.64)** -0.008 (1.16) 0.003 (0.42) -0.022 (0.70) -0.000 (1.28) -1.130 (1.73)* -457.41 -0.782 (1.15) -455.61 3.61 (0.0575)* -0.664 (0.98) -454.36 6.11 (0.0135)** -1.135 (1.73) -457.41 0 (0.951) -0.981 (1.46) -457.01 0.82 (0.366) 0.000 (0.39) -1.127 (1.73) -457.34 0.15 (0.698) 134.23 [115.55 154.06] 0.29 134.64 [117.88 154.12] 0.27 134.89 [118.04 154.12] 0.27 134.23 [120.45 0.26 154.76] 134.32 [120.48 154.8] 0.26 134.24 [120.47 154.74] 0.26 output _gdpgwr Constant H4 -0.005 (13.01)** -0.263 (2.34)* 0.083 (0.80) 0.355 (6.68)** 0.369 (3.59)** -0.002 (0.40) -0.000 (0.00) 0.055 (4.07)** 0.182 (1.45) 0.030 (0.31) -0.083 (0.47) -0.034 (0.21) 0.180 (1.51) 0.135 (3.34)** -0.003 (0.45) -0.004 (0.55) -0.018 (0.57) H5 -0.005 (13.01)** -0.267 (2.38)* 0.091 (0.88) 0.349 (6.58)** 0.369 (3.59)** -0.002 (0.40) 0.001 (0.05) 0.055 (4.10)** 0.191 (1.52) 0.031 (0.32) -0.074 (0.42) -0.007 (0.04) 0.169 (1.41) 0.140 (3.45)** -0.004 (0.68) -0.000 (0.08) -0.016 (0.52) -0.000 (0.36) H5 -0.005 (13.00)** -0.268 (2.39)* 0.099 (0.95) 0.344 (6.50)** 0.357 (3.46)** -0.002 (0.40) 0.002 (0.15) 0.056 (4.15)** 0.203 (1.61) 0.032 (0.33) -0.064 (0.36) 0.024 (0.14) 0.160 (1.34) 0.147 (3.60)** -0.007 (1.06) 0.002 (0.28) -0.018 (0.58) -0.924 (1.37) -456.6 1.63 (0.201) -1.115 (1.71) -457.35 0.13 (0.718) -0.000 (1.14) -1.009 (1.53) -456.76 1.31 (0.252) 134.48 [121.06 154.95] 0.25 134.26 [120.43 154.74] 0.26 134.39 [120.88 154.89] 0.25 Tables A6.6 Robustness check: substitute variable: distance weighted aggregate Industrial Output(continue) Bid price rep_gov water_problem will_service quality_deg age education income_level Income significant higher than need male Can see the river Far from the river d_fish Degree share2nd pop_density gdp_growth H1 -0.008 (23.33)*** -0.236 (2.34)** -0.014 (0.15) 0.355 (7.57)*** 0.235 (2.55)** -0.003 (0.65) -0.009 (0.70) 0.059 (4.98)*** 0.202 (1.82)* -0.060 (0.69) -0.239 (1.53) -0.169 (1.17) 0.187 (1.76)* 0.137 (3.85)*** -0.004 (0.89) -0.002 (0.48) -0.019 (0.70) Total Output H2 -0.008 (23.28)*** -0.245 (2.43)** -0.009 (0.09) 0.347 (7.32)*** 0.224 (2.41)** -0.003 (0.68) -0.007 (0.52) 0.060 (5.02)*** 0.212 (1.91)* -0.061 (0.69) -0.223 (1.42) -0.132 (0.89) 0.180 (1.68)* 0.139 (3.89)*** -0.006 (1.13) -0.001 (0.18) -0.029 (1.02) -1.0610-7 (1.28) H3 -0.008 (23.43)*** -0.237 (2.35)** 0.002 (0.03) 0.345 (7.30)*** 0.203 (2.17)** -0.003 (0.66) -0.005 (0.39) 0.061 (5.09)*** 0.223 (2.01)** -0.063 (0.71) -0.214 (1.37) -0.102 (0.68) 0.173 (1.62) 0.151 (4.13)*** -0.010 (1.75)* 0.000 (0.03) -0.031 (1.09) -0.000012 (2.05)** output_pop H4 -0.008 (23.21)** -0.234 (2.32)* -0.015 (0.16) 0.356 (7.52)** 0.235 (2.54)* -0.003 (0.65) -0.009 (0.69) 0.059 (4.98)** 0.200 (1.80) -0.061 (0.69) -0.241 (1.54) -0.174 (1.17) 0.189 (1.76) 0.136 (3.71)** -0.004 (0.79) -0.003 (0.43) -0.019 (0.69) 0.000 (0.15) output _gdppc Double Bound H4 -0.008 (23.37)** -0.234 (2.32)* -0.019 (0.21) 0.359 (7.58)** 0.229 (2.47)* -0.003 (0.66) -0.010 (0.73) 0.060 (4.99)** 0.196 (1.76) -0.060 (0.69) -0.245 (1.56) -0.187 (1.27) 0.196 (1.82) 0.136 (3.79)** -0.005 (0.91) -0.005 (0.76) -0.023 (0.82) 0.000 (0.60) output _gdpgwr Constant Log likelihood LR Mean WTP KR CI Ratio -0.516 (0.89) -1045.41 103.43 [92.41 114.66] 0.22 -0.307 (0.51) -1044.59 1.64 (0.2008) 103.58 [93.90 113.93] 0.19 -0.172 (0.29) -1043.30 4.21 (0.0420)** 103.64 [91.97 113.97] 0.19 -0.524 (0.90) -1045.4 21.83 (0.884) 103.43 [94.95 114.65] 0.19 -0.427 (0.72) -1045.23 28.59 (0.549) 103.51 [94.82 114.67] 0.19 H4 -0.008 (23.37)** -0.235 (2.33)* -0.015 (0.16) 0.356 (7.52)** 0.235 (2.55)* -0.003 (0.65) -0.009 (0.71) 0.059 (4.97)** 0.199 (1.80) -0.061 (0.69) -0.242 (1.54) -0.177 (1.19) 0.190 (1.77) 0.136 (3.76)** -0.004 (0.79) -0.003 (0.49) -0.020 (0.72) H5 -0.008 (23.65)** -0.241 (2.39)* -0.004 (0.04) 0.349 (7.38)** 0.225 (2.43)* -0.003 (0.63) -0.008 (0.62) 0.060 (5.03)** 0.213 (1.92) -0.059 (0.67) -0.224 (1.43) -0.131 (0.88) 0.175 (1.63) 0.148 (3.98)** -0.008 (1.31) 0.001 (0.23) -0.023 (0.83) -0.000 (1.07) 0.000 (0.21) -0.513 (0.89) -1045.38 35.04 (0.833) 103.44 [94.91 114.61] 0.19 -0.369 (0.62) -1044.83 23.22 (0.285) 103.49 [95.2 114.71] 0.19 H5 -0.008 (23.45)** -0.237 (2.36)* -0.009 (0.10) 0.352 (7.45)** 0.233 (2.53)* -0.003 (0.64) -0.009 (0.65) 0.060 (5.00)** 0.206 (1.86) -0.060 (0.68) -0.234 (1.50) -0.154 (1.03) 0.181 (1.69) 0.141 (3.85)** -0.005 (0.99) -0.001 (0.11) -0.019 (0.68) -0.000 (0.43) -0.502 (0.87) -1045.31 27.71 (0.665) 103.41 [94.96 114.58] 0.19 H5 -0.008 (23.48)** -0.237 (2.36)* -0.004 (0.04) 0.349 (7.38)** 0.223 (2.41)* -0.003 (0.65) -0.007 (0.56) 0.060 (5.04)** 0.214 (1.92) -0.060 (0.68) -0.226 (1.45) -0.130 (0.87) 0.175 (1.63) 0.146 (3.98)** -0.007 (1.30) 0.001 (0.18) -0.021 (0.74) -0.000 (1.08) -0.418 (0.72) -1044.82 28.46 (0.279) 103.45 [95.13 114.66] 0.19 Tables A6.7 Robustness check: substitute variable: stage Bid price rep_gov water_problem will_service quality_deg age education income_level Income significant higher than need male Can see the river Far from the river d_fish Degree share2nd pop_density gdp_growth H1 -0.025 (34.88)*** -0.226 (2.50)** 0.038 (0.48) 0.165 (3.95)*** 0.233 (2.86)*** -0.001 (0.39) 0.011 (0.85) 0.051 (4.63)*** 0.300 (3.06)*** -0.042 (0.54) -0.080 (0.59) -0.100 (0.78) 0.121 (1.27) 0.184 (5.46)*** -0.001 (0.23) -0.027 (7.07)*** -0.013 (0.53) Stage H2 -0.025 (34.88)*** -0.226 (2.50)** 0.103 (1.28) 0.124 (2.92)*** 0.191 (2.35)** -0.001 (0.36) 0.013 (0.98) 0.058 (5.24)*** 0.307 (3.12)*** -0.048 (0.62) -0.041 (0.30) -0.039 (0.31) 0.154 (1.61) 0.167 (4.92)*** -0.006 (1.34) -0.025 (6.28)*** -0.013 (0.53) -0.083 (5.45)*** H3 -0.025 (34.87)*** -0.222 (2.46)** 0.089 (1.10) 0.133 (3.13)*** 0.197 (2.42)** -0.001 (0.40) 0.013 (0.98) 0.057 (5.19)*** 0.297 (3.02)*** -0.047 (0.61) -0.051 (0.38) -0.055 (0.43) 0.152 (1.58) 0.181 (5.37)*** -0.007 (1.57) -0.025 (6.33)*** -0.018 (0.74) -0.096 (4.50)*** stage_pop H4 -0.025 (34.89)** -0.227 (2.52)* 0.059 (0.74) 0.124 (2.92)** 0.227 (2.80)** -0.001 (0.40) 0.004 (0.34) 0.055 (5.02)** 0.328 (3.33)** -0.068 (0.88) -0.047 (0.35) -0.088 (0.69) 0.139 (1.45) 0.181 (5.35)** -0.002 (0.53) -0.029 (7.38)** -0.060 (2.30)* Def Yes H4 -0.025 (34.87)** -0.257 (2.84)** 0.098 (1.21) 0.123 (2.89)** 0.242 (2.98)** -0.001 (0.27) 0.010 (0.80) 0.053 (4.83)** 0.313 (3.19)** -0.047 (0.61) -0.070 (0.52) -0.094 (0.74) 0.143 (1.50) 0.177 (5.25)** -0.009 (2.02)* -0.029 (7.45)** -0.005 (0.19) -0.087 (5.56)** stage_gdppc Log likelihood LR Mean WTP KR CI Ratio H5 -0.025 (34.89)** -0.227 (2.52)* 0.064 (0.80) 0.132 (3.11)** 0.237 (2.92)** -0.002 (0.45) 0.007 (0.50) 0.054 (4.96)** 0.313 (3.19)** -0.055 (0.71) -0.064 (0.48) -0.088 (0.68) 0.137 (1.43) 0.196 (5.80)** -0.006 (1.27) -0.028 (7.20)** -0.049 (1.90) -0.079 (4.62)** -0.306 (0.58) -2184.30 27.21 [24.09 30.44] 0.23 0.179 (0.34) -2169.14 29.73 (0.000)*** 27.30 [24.50 30.22] 0.21 0.186 (0.35) -2174.19 20.22 (0.000) *** 27.28 [24.47 30.22] 0.21 0.840 (1.50) -2168.79 31.02 (0.000)*** 27.26 [25.26 30.37] 0.19 H5 -0.025 (34.87)** -0.236 (2.62)** 0.093 (1.16) 0.125 (2.95)** 0.212 (2.60)** -0.001 (0.39) 0.012 (0.90) 0.057 (5.17)** 0.299 (3.05)** -0.051 (0.66) -0.057 (0.43) -0.071 (0.56) 0.153 (1.60) 0.184 (5.45)** -0.009 (1.97)* -0.027 (6.83)** -0.026 (1.04) H5 -0.025 (34.87)** -0.227 (2.52)* 0.091 (1.13) 0.131 (3.10)** 0.195 (2.39)* -0.002 (0.42) 0.014 (1.07) 0.058 (5.28)** 0.296 (3.02)** -0.053 (0.68) -0.057 (0.42) -0.062 (0.49) 0.160 (1.67) 0.184 (5.46)** -0.008 (1.85) -0.024 (6.20)** -0.029 (1.18) -0.108 (4.59)** stage_gdpgwr Constant H4 -0.025 (34.87)** -0.233 (2.59)** 0.104 (1.29) 0.123 (2.90)** 0.189 (2.32)* -0.001 (0.40) 0.014 (1.09) 0.059 (5.38)** 0.306 (3.11)** -0.055 (0.71) -0.048 (0.35) -0.048 (0.37) 0.163 (1.71) 0.171 (5.06)** -0.008 (1.72) -0.024 (6.13)** -0.029 (1.17) 0.335 (0.62) -2173.63 21.34 (0.000)*** 27.27 [25.25 30.41] 0.19 -0.127 (4.64)** -0.070 (5.41)** 0.441 (0.82) -2169.64 29.32 (0.000)*** 27.3 [25.32 30.43] 0.19 0.664 (1.18) -2173.72 21.18 (0.000)*** 27.25 [25.24 30.39] 0.19 0.476 (0.87) -2173.55 21.50 (0.000)*** 27.28 [25.28 30.42] 0.19 -0.080 (4.45)** 0.374 (0.69) -2174.41 19.78 (0.000)*** 27.28 [25.29 30.43] 0.19 Tables A6.8 Robustness check: substitute variable: stage (continue) Bid price rep_gov water_problem will_service quality_deg age education income_level Income significant higher than need male Can see the river Far from the river d_fish Degree share2nd pop_density gdp_growth H1 -0.016 (36.10)*** -0.310 (3.45)*** 0.027 (0.34) 0.169 (4.09)*** 0.305 (3.77)*** -0.003 (0.95) 0.002 (0.12) 0.039 (3.62)*** 0.371 (3.79)*** 0.026 (0.34) -0.163 (1.22) -0.191 (1.51) 0.180 (1.89)* 0.137 (4.11)*** -0.005 (1.21) -0.022 (5.59)*** 0.057 (2.31)** Stage H2 -0.017 (36.08)*** -0.313 (3.47)*** 0.096 (1.20) 0.127 (3.01)*** 0.265 (3.26)*** -0.003 (0.91) 0.003 (0.26) 0.047 (4.26)*** 0.382 (3.90)*** 0.020 (0.26) -0.121 (0.91) -0.129 (1.02) 0.217 (2.27)** 0.119 (3.56)*** -0.010 (2.38)** -0.018 (4.75)*** 0.059 (2.40)** -0.088 (5.78)*** H3 -0.017 (36.08)*** -0.308 (3.43)*** 0.086 (1.08) 0.133 (3.16)*** 0.267 (3.29)*** -0.003 (0.96) 0.004 (0.28) 0.047 (4.27)*** 0.371 (3.79)*** 0.020 (0.26) -0.129 (0.97) -0.141 (1.11) 0.217 (2.27)** 0.134 (4.03)*** -0.012 (2.73)*** -0.018 (4.74)*** 0.053 (2.14)** -0.111 (5.24)*** stage_pop H4 -0.017 (36.10)** -0.312 (3.46)** 0.041 (0.51) 0.143 (3.40)** 0.302 (3.73)** -0.003 (0.95) -0.002 (0.18) 0.042 (3.83)** 0.389 (3.96)** 0.010 (0.13) -0.141 (1.06) -0.183 (1.44) 0.191 (2.00)* 0.134 (4.03)** -0.006 (1.39) -0.022 (5.75)** 0.029 (1.11) Prob Yes H4 -0.017 (36.10)** -0.322 (3.57)** 0.051 (0.64) 0.152 (3.58)** 0.308 (3.80)** -0.003 (0.90) 0.001 (0.10) 0.040 (3.68)** 0.376 (3.83)** 0.024 (0.32) -0.158 (1.19) -0.189 (1.49) 0.188 (1.97)* 0.134 (4.01)** -0.008 (1.83) -0.022 (5.71)** 0.060 (2.44)* -0.053 (3.47)** stage_gdppc Log likelihood LR Mean WTP KR CI Ratio H5 -0.017 (36.09)** -0.312 (3.47)** 0.046 (0.58) 0.145 (3.45)** 0.309 (3.82)** -0.004 (0.99) -0.002 (0.12) 0.042 (3.84)** 0.382 (3.89)** 0.017 (0.22) -0.150 (1.13) -0.182 (1.43) 0.192 (2.01)* 0.145 (4.36)** -0.008 (1.93) -0.022 (5.66)** 0.032 (1.23) -0.031 (1.84) -0.557 (1.07) -2202.27 52.68 [48.00 57.48] 0.18 -0.078 (0.15) -2185.53 33.49 (0.000) *** 52.72 [48.62 56.99] 0.16 -0.016 (0.03) -2188.56 27.42 (0.000) *** 52.71 [48.60 57.01] 0.16 0.132 (0.24) -2196.26 12.02 (0.000)*** 52.69 [49.58 57.43] 0.15 H5 -0.017 (36.09)** -0.320 (3.55)** 0.074 (0.93) 0.136 (3.21)** 0.288 (3.56)** -0.003 (0.95) 0.002 (0.17) 0.045 (4.06)** 0.372 (3.79)** 0.019 (0.24) -0.143 (1.07) -0.168 (1.32) 0.207 (2.17)* 0.137 (4.10)** -0.012 (2.61)** -0.021 (5.36)** 0.047 (1.90) H5 -0.017 (36.08)** -0.314 (3.49)** 0.090 (1.12) 0.131 (3.10)** 0.264 (3.25)** -0.004 (0.98) 0.005 (0.38) 0.048 (4.40)** 0.370 (3.78)** 0.013 (0.17) -0.135 (1.01) -0.149 (1.17) 0.227 (2.37)* 0.138 (4.13)** -0.014 (3.05)** -0.018 (4.60)** 0.040 (1.59) -0.077 (3.34)** stage_gdpgwr Constant H4 -0.017 (36.08)** -0.320 (3.56)** 0.097 (1.22) 0.125 (2.97)** 0.262 (3.22)** -0.003 (0.96) 0.005 (0.37) 0.049 (4.41)** 0.381 (3.88)** 0.012 (0.16) -0.128 (0.96) -0.138 (1.09) 0.227 (2.37)* 0.124 (3.71)** -0.012 (2.77)** -0.018 (4.59)** 0.042 (1.71) -0.309 (0.58) -2200.59 3.37 (0.001)*** 52.68 [49.51 57.46] 0.15 -0.107 (3.94)** -0.075 (5.77)** 0.204 (0.38) -2185.63 33.29 (0.066)** 52.71 [49.67 57.36] 0.15 0.125 (0.22) -2196.69 11.17 (0.000)*** 52.69 [49.58 57.43] 0.15 0.085 (0.16) -2194.49 15.56 (0.000)*** 52.7 [49.6 57.42] 0.15 -0.094 (5.22)** 0.211 (0.39) -2188.64 27.27 (0.000)*** 52.71 [49.65 57.38] 0.15 Tables A6.9 Robustness check: substitute variable: stage (continue) Bid price rep_gov water_problem will_service quality_deg age education income_level Income significant higher than need male Can see the river Far from the river d_fish Degree share2nd pop_density gdp_growth H1 -0.009 (36.11)*** -0.126 (1.41) 0.067 (0.86) 0.167 (4.04)*** 0.222 (2.76)*** -0.003 (0.73) -0.003 (0.27) 0.036 (3.28)*** 0.291 (2.99)*** -0.054 (0.70) -0.325 (2.43)** -0.395 (3.11)*** 0.057 (0.60) 0.049 (1.49) -0.011 (2.71)*** -0.009 (2.30)** 0.117 (4.74)*** Stage H2 -0.009 (36.11)*** -0.123 (1.38) 0.121 (1.52) 0.133 (3.17)*** 0.189 (2.34)** -0.003 (0.69) -0.002 (0.17) 0.041 (3.75)*** 0.297 (3.04)*** -0.060 (0.78) -0.295 (2.21)** -0.350 (2.75)*** 0.082 (0.87) 0.034 (1.01) -0.016 (3.58)*** -0.006 (1.58) 0.119 (4.83)*** -0.068 (4.50)*** H3 -0.009 (36.11)*** -0.121 (1.35) 0.117 (1.47) 0.136 (3.25)*** 0.189 (2.34)** -0.003 (0.73) -0.002 (0.15) 0.042 (3.80)*** 0.289 (2.97)*** -0.060 (0.78) -0.300 (2.24)** -0.357 (2.80)*** 0.085 (0.89) 0.045 (1.38) -0.017 (3.89)*** -0.006 (1.54) 0.114 (4.62)*** -0.092 (4.36)*** stage_pop H4 -0.009 (36.11)** -0.125 (1.40) 0.076 (0.97) 0.149 (3.54)** 0.220 (2.73)** -0.003 (0.73) -0.006 (0.48) 0.037 (3.41)** 0.302 (3.10)** -0.065 (0.85) -0.311 (2.33)* -0.390 (3.07)** 0.063 (0.66) 0.047 (1.42) -0.012 (2.83)** -0.009 (2.39)* 0.098 (3.78)** Not Sure H4 -0.009 (36.11)** -0.136 (1.51) 0.088 (1.11) 0.152 (3.58)** 0.225 (2.79)** -0.003 (0.69) -0.004 (0.29) 0.036 (3.33)** 0.295 (3.02)** -0.056 (0.72) -0.321 (2.41)* -0.394 (3.10)** 0.063 (0.67) 0.046 (1.40) -0.014 (3.12)** -0.009 (2.41)* 0.120 (4.85)** -0.036 (2.38)* stage_gdppc Log likelihood LR Mean WTP KR CI Ratio H5 -0.009 (36.11)** -0.126 (1.41) 0.081 (1.02) 0.150 (3.56)** 0.225 (2.79)** -0.003 (0.75) -0.006 (0.44) 0.037 (3.42)** 0.298 (3.05)** -0.061 (0.80) -0.317 (2.37)* -0.389 (3.06)** 0.064 (0.67) 0.055 (1.66) -0.014 (3.18)** -0.009 (2.33)* 0.099 (3.84)** -0.027 (1.62) -0.749 (1.44) -2312.00 92.56 [84.07 101.28] 0.19 -0.379 (0.72) -2301.86 20.28 (0.000)*** 92.58 [85.07 100.48] 0.17 -0.303 (0.57) -2302.51 18.99 (0.000)*** 92.58 [85.06 100.48] 0.17 -0.279 (0.50) -2309.18 5.65 (0.018)** 92.56 [86.9 101.16] 0.15 H5 -0.009 (36.11)** -0.132 (1.48) 0.112 (1.40) 0.135 (3.21)** 0.206 (2.56)* -0.003 (0.73) -0.003 (0.23) 0.040 (3.68)** 0.291 (2.98)** -0.061 (0.80) -0.309 (2.31)* -0.376 (2.96)** 0.081 (0.85) 0.048 (1.45) -0.018 (3.90)** -0.008 (2.04)* 0.108 (4.37)** H5 -0.009 (36.11)** -0.126 (1.41) 0.128 (1.60) 0.130 (3.10)** 0.182 (2.25)* -0.003 (0.75) -0.000 (0.03) 0.044 (4.00)** 0.289 (2.96)** -0.067 (0.88) -0.303 (2.27)* -0.360 (2.83)** 0.098 (1.03) 0.048 (1.46) -0.020 (4.35)** -0.005 (1.32) 0.101 (4.08)** -0.055 (2.41)* stage_gdpgwr Constant H4 -0.009 (36.11)** -0.130 (1.46) 0.130 (1.63) 0.128 (3.04)** 0.182 (2.25)* -0.003 (0.73) -0.001 (0.06) 0.043 (3.96)** 0.297 (3.04)** -0.067 (0.88) -0.298 (2.23)* -0.353 (2.77)** 0.095 (0.99) 0.036 (1.08) -0.018 (4.02)** -0.005 (1.36) 0.105 (4.24)** -0.531 (0.99) -2310.69 2.61 (0.106) 92.56 [86.83 101.18] 0.16 -0.100 (3.70)** -0.066 (5.09)** -0.083 (0.16) -2299.03 25.95 (0.000)*** 92.58 [87.01 101.08] 0.15 -0.260 (0.47) -2309.10 5.80 (0.000)*** 92.57 [86.9 101.17] 0.15 -0.150 (0.28) -2305.16 13.68 (0.000)*** 92.57 [86.93 101.13] 0.15 -0.089 (4.96)** -0.025 (0.05) -2299.70 24.60 (0.000)*** 92.58 [86.99 101.09] 0.15 Tables A6.10 Robustness check: substitute variable: stage (continue) Bid price rep_gov water_problem will_service quality_deg age education income_level Income significant higher than need male Can see the river Far from the river d_fish Degree share2nd pop_density gdp_growth H1 -0.005 (13.01)*** -0.265 (2.37)** 0.087 (0.84) 0.352 (6.69)*** 0.370 (3.60)*** -0.002 (0.40) 0.000 (0.02) 0.055 (4.09)*** 0.187 (1.49) 0.031 (0.32) -0.079 (0.45) -0.020 (0.12) 0.174 (1.47) 0.137 (3.45)*** -0.003 (0.58) -0.002 (0.38) -0.017 (0.54) Stage H2 -0.005 (13.03)*** -0.275 (2.45)** 0.104 (1.00) 0.333 (6.25)*** 0.356 (3.45)*** -0.002 (0.47) 0.008 (0.50) 0.056 (4.16)*** 0.209 (1.66)* 0.022 (0.23) -0.044 (0.25) 0.061 (0.37) 0.154 (1.29) 0.129 (3.20)*** -0.005 (0.82) -0.001 (0.12) -0.018 (0.60) -0.046 (2.34)** H3 -0.005 (13.05)*** -0.275 (2.45)** 0.110 (1.06) 0.332 (6.23)*** 0.342 (3.31)*** -0.002 (0.44) 0.008 (0.56) 0.057 (4.19)*** 0.215 (1.70)* 0.019 (0.20) -0.040 (0.23) 0.072 (0.43) 0.151 (1.27) 0.139 (3.45)*** -0.007 (1.15) -0.000 (0.04) -0.021 (0.68) -0.077 (2.70)*** stage_pop H4 -0.005 (13.07)** -0.287 (2.55)* 0.093 (0.90) 0.336 (6.32)** 0.362 (3.51)** -0.002 (0.49) 0.005 (0.31) 0.055 (4.12)** 0.200 (1.59) 0.020 (0.21) -0.042 (0.24) 0.027 (0.16) 0.159 (1.34) 0.139 (3.45)** -0.004 (0.67) -0.003 (0.60) -0.034 (1.05) Single Bound H4 -0.005 (13.01)** -0.268 (2.40)* 0.097 (0.93) 0.348 (6.61)** 0.373 (3.63)** -0.002 (0.42) 0.001 (0.06) 0.055 (4.08)** 0.195 (1.55) 0.034 (0.35) -0.072 (0.41) -0.002 (0.01) 0.172 (1.45) 0.135 (3.36)** -0.005 (0.82) -0.002 (0.47) -0.013 (0.43) -0.038 (2.05)* stage_gdppc Log likelihood LR Mean WTP KR CI Ratio H5 -0.005 (13.08)** -0.291 (2.58)** 0.106 (1.02) 0.333 (6.28)** 0.353 (3.41)** -0.002 (0.45) 0.005 (0.37) 0.056 (4.12)** 0.206 (1.63) 0.018 (0.18) -0.033 (0.19) 0.047 (0.29) 0.158 (1.33) 0.150 (3.68)** -0.006 (1.04) -0.003 (0.55) -0.040 (1.24) -0.019 (0.81) -1.130 (1.73)* -457.41 134.23 [115.55 0.29 154.06] -0.976 (1.49) -454.66 5.50 (0.0190)** 134.53 [117.82 0.27 153.62] -0.905 (1.37) -453.75 7.33 (0.0068)*** 134.72 [118.01 153.94] 0.27 -0.773 (1.14) -455.29 4.25 (0.039)** 134.68 [121.8 0.25 155.26] H5 -0.005 (13.03)** -0.273 (2.44)* 0.115 (1.10) 0.336 (6.35)** 0.353 (3.42)** -0.002 (0.47) 0.006 (0.38) 0.056 (4.15)** 0.214 (1.69) 0.028 (0.28) -0.049 (0.28) 0.055 (0.33) 0.156 (1.31) 0.139 (3.45)** -0.008 (1.34) -0.002 (0.33) -0.023 (0.75) H5 -0.005 (13.02)** -0.270 (2.41)* 0.109 (1.05) 0.333 (6.27)** 0.338 (3.26)** -0.002 (0.46) 0.008 (0.53) 0.057 (4.21)** 0.216 (1.71) 0.023 (0.23) -0.040 (0.23) 0.074 (0.44) 0.154 (1.29) 0.140 (3.49)** -0.008 (1.31) 0.000 (0.03) -0.029 (0.92) -0.079 (2.71)** stage_gdpgwr Constant H4 -0.005 (13.01)** -0.272 (2.43)* 0.101 (0.97) 0.334 (6.29)** 0.351 (3.40)** -0.002 (0.49) 0.007 (0.46) 0.057 (4.18)** 0.209 (1.66) 0.025 (0.26) -0.046 (0.26) 0.058 (0.35) 0.157 (1.32) 0.131 (3.25)** -0.005 (0.94) -0.000 (0.07) -0.026 (0.84) -1.053 (1.59) -457.08 0.66 (0.415) 134.22 [120.76 154.76] 0.25 -0.105 (2.39)* -0.037 (2.23)* -0.855 (1.28) -454.93 4.97 (0.026)** 134.57 [121.66 155.16] 0.25 -0.642 (0.94) -453.67 7.49 (0.006)*** 134.97 [122.03 155.48] 0.25 -0.774 (1.15) -454.54 5.74 (0.017)** 134.63 [121.7 155.14] 0.25 -0.064 (2.61)** -0.770 (1.15) -453.99 6.85 (0.009)*** 134.77 [121.81 155.34] 0.25 Tables A6.11 Robustness check: substitute variable: stage (continue) Bid price rep_gov water_problem will_service quality_deg age education income_level Income significant higher than need male Can see the river Far from the river d_fish Degree share2nd pop_density gdp_growth H1 -0.008 (23.33)*** -0.236 (2.34)** -0.014 (0.15) 0.355 (7.57)*** 0.235 (2.55)** -0.003 (0.65) -0.009 (0.70) 0.059 (4.98)*** 0.202 (1.82)* -0.060 (0.69) -0.239 (1.53) -0.169 (1.17) 0.187 (1.76)* 0.137 (3.85)*** -0.004 (0.89) -0.002 (0.48) -0.019 (0.70) Stage H2 -0.008 (23.39)*** -0.241 (2.40)** -0.005 (0.05) 0.342 (7.19)*** 0.223 (2.41)** -0.003 (0.71) -0.004 (0.31) 0.060 (5.04)*** 0.218 (1.96)* -0.066 (0.75) -0.215 (1.37) -0.106 (0.71) 0.176 (1.64)* 0.131 (3.64)*** -0.005 (1.08) -0.001 (0.26) -0.020 (0.73) -0.033 (1.84)* H3 -0.008 (23.35)*** -0.240 (2.39)** 0.000 (0.00) 0.340 (7.18)*** 0.213 (2.30)** -0.003 (0.68) -0.003 (0.26) 0.061 (5.06)*** 0.222 (2.00)** -0.068 (0.78) -0.212 (1.35) -0.098 (0.65) 0.173 (1.62) 0.138 (3.85)*** -0.007 (1.34) -0.001 (0.19) -0.022 (0.80) -0.056 (2.16)** stage_pop H4 -0.008 (23.48)** -0.249 (2.47)* -0.009 (0.10) 0.344 (7.26)** 0.228 (2.47)* -0.003 (0.72) -0.007 (0.49) 0.060 (5.02)** 0.209 (1.89) -0.067 (0.76) -0.217 (1.39) -0.135 (0.92) 0.177 (1.66) 0.138 (3.86)** -0.005 (0.97) -0.003 (0.63) -0.030 (1.04) Double Bound H4 -0.008 (23.42)** -0.239 (2.38)* -0.005 (0.05) 0.352 (7.49)** 0.236 (2.56)* -0.003 (0.66) -0.009 (0.65) 0.060 (4.99)** 0.208 (1.88) -0.057 (0.65) -0.234 (1.50) -0.149 (1.01) 0.184 (1.72) 0.135 (3.75)** -0.006 (1.12) -0.002 (0.56) -0.016 (0.58) -0.025 (1.50) stage_gdppc Log likelihood LR Mean WTP KR CI Ratio H5 -0.008 (23.32)** -0.252 (2.50)* -0.001 (0.01) 0.342 (7.22)** 0.220 (2.38)* -0.003 (0.69) -0.006 (0.43) 0.060 (5.01)** 0.215 (1.94) -0.069 (0.78) -0.209 (1.33) -0.117 (0.79) 0.176 (1.64) 0.146 (4.04)** -0.007 (1.27) -0.003 (0.59) -0.035 (1.21) -0.018 (0.86) -0.516 (0.89) -1045.41 103.43 [92.41 114.66] 0.22 -0.410 (0.71) -1043.72 3.38 (0.0660)* 103.58 [93.88 113.91] 0.19 -0.360 (0.62) -1043.08 4.65 (0.0311)** 103.65 [93.97 113.98] 0.19 -0.284 (0.48) -1044.27 2.26 (0.132) 103.6 [95.91 115.14] 0.19 H5 -0.008 (23.33)** -0.242 (2.40)* 0.007 (0.07) 0.343 (7.26)** 0.218 (2.36)* -0.003 (0.70) -0.005 (0.37) 0.061 (5.06)** 0.222 (2.00)* -0.062 (0.71) -0.216 (1.38) -0.101 (0.68) 0.172 (1.61) 0.138 (3.86)** -0.008 (1.55) -0.002 (0.41) -0.024 (0.87) H5 -0.008 (23.33)** -0.238 (2.37)* -0.000 (0.00) 0.341 (7.20)** 0.210 (2.26)* -0.003 (0.70) -0.004 (0.27) 0.061 (5.08)** 0.223 (2.00)* -0.066 (0.75) -0.211 (1.35) -0.094 (0.63) 0.174 (1.63) 0.140 (3.89)** -0.008 (1.46) -0.001 (0.12) -0.028 (1.01) -0.056 (2.13)* stage_gdpgwr Constant H4 -0.008 (23.52)** -0.241 (2.39)* -0.006 (0.07) 0.343 (7.22)** 0.219 (2.37)* -0.003 (0.72) -0.005 (0.34) 0.061 (5.06)** 0.217 (1.95) -0.064 (0.73) -0.216 (1.38) -0.108 (0.72) 0.177 (1.66) 0.132 (3.69)** -0.006 (1.17) -0.001 (0.22) -0.026 (0.93) -0.445 (0.76) -1045.04 0.74 (0.391) 103.39 [95.35 114.71] 0.19 -0.086 (2.13)* -0.027 (1.76) -0.321 (0.55) -1043.85 3.11 (0.078)* 103.58 [95.78 115.14] 0.19 -0.178 (0.30) -1043.12 4.57 (0.032)** 103.72 [96 115.23] 0.19 -0.238 (0.40) -1043.14 4.54 (0.033)** 103.55 [95.68 114.99] 0.19 -0.047 (2.12)* -0.257 (0.44) -1043.15 4.50 (0.034)** 103.64 [95.79 115.18] 0.19 Tables A6.12 Robustness check: substitute variable: stage (continue) Bid price rep_gov water_problem will_service quality_deg age education income_level Income significant higher than need male Can see the river Far from the river d_fish Degree share2nd pop_density gdp_growth H1 -0.011 (38.13)*** -18.436 (2.19)** 7.080 (0.95) 15.093 (3.87)*** 20.245 (2.67)*** -0.271 (0.79) -0.554 (0.46) 4.019 (3.96)*** 27.176 (2.96)*** -5.829 (0.81) -25.250 (2.02)** -28.295 (2.38)** 10.770 (1.20) 5.134 (1.65)* -0.917 (2.29)** -1.011 (2.83)*** 9.605 (4.16)*** Stage H2 -0.011 (38.13)*** -17.912 (2.16)** 12.432 (1.68)* 11.499 (2.94)*** 16.514 (2.20)** -0.255 (0.76) -0.433 (0.36) 4.503 (4.48)*** 27.268 (3.02)*** -6.344 (0.89) -21.916 (1.77)* -23.241 (1.98)** 13.263 (1.50) 3.462 (1.12) -1.303 (3.24)*** -0.728 (2.04)** 9.641 (4.24)*** -6.757 (4.87)*** H3 -0.011 (38.13)*** -17.669 (2.13)** 11.950 (1.61) 11.844 (3.03)*** 16.596 (2.21)** -0.269 (0.80) -0.406 (0.34) 4.565 (4.53)*** 26.538 (2.94)*** -6.381 (0.89) -22.413 (1.81)* -24.003 (2.04)** 13.488 (1.52) 4.646 (1.51) -1.477 (3.58)*** -0.720 (2.01)** 9.140 (4.01)*** -9.108 (4.66)*** stage_pop H4 -0.011 (38.13)** -18.284 (2.18)* 7.961 (1.07) 13.287 (3.36)** 19.901 (2.64)** -0.270 (0.79) -0.820 (0.68) 4.151 (4.10)** 28.107 (3.07)** -6.902 (0.96) -23.813 (1.91) -27.675 (2.33)* 11.384 (1.27) 4.851 (1.56) -0.963 (2.41)* -1.038 (2.91)** 7.723 (3.18)** Wang & He H4 -0.011 (38.13)** -19.178 (2.27)* 8.632 (1.14) 13.966 (3.49)** 20.698 (2.73)** -0.253 (0.74) -0.575 (0.48) 4.024 (3.97)** 27.422 (2.99)** -5.939 (0.82) -25.082 (2.00)* -28.317 (2.38)* 11.185 (1.25) 4.986 (1.60) -1.130 (2.59)** -1.052 (2.93)** 9.847 (4.25)** -3.510 (2.45)* stage_gdppc Log likelihood LR Mean WTP KR CI Ratio H5 -0.011 (38.13)** -18.323 (2.18)* 8.423 (1.13) 13.287 (3.37)** 20.356 (2.70)** -0.279 (0.82) -0.780 (0.65) 4.171 (4.12)** 27.701 (3.03)** -6.505 (0.90) -24.359 (1.95) -27.554 (2.32)* 11.493 (1.29) 5.641 (1.81) -1.142 (2.80)** -1.016 (2.85)** 7.776 (3.23)** -2.317 (1.23) -62.418 (1.27) -4344.03 75.99 [68.89 83.48] 0.19 -23.962 (0.49) -4332.38 23.30 (0.000)*** 75.99 [69.62 82.872] 0.17 -17.051 (0.35) -4333.34 21.37 (0.000)*** 75.99 [69.62 82.88] 0.17 -16.570 (0.32) -4341.04 5.98 (0.014)** 75.99 [71.14 83.44] 0.16 H5 -0.011 (38.13)** -18.976 (2.27)* 11.204 (1.50) 11.929 (3.02)** 18.963 (2.53)* -0.261 (0.77) -0.537 (0.45) 4.392 (4.34)** 26.840 (2.95)** -6.504 (0.91) -23.689 (1.91) -26.435 (2.24)* 12.798 (1.44) 5.087 (1.65) -1.516 (3.53)** -0.928 (2.61)** 8.608 (3.74)** H5 -0.011 (38.13)** -18.149 (2.19)* 12.786 (1.73) 11.319 (2.91)** 15.976 (2.14)* -0.276 (0.82) -0.265 (0.22) 4.766 (4.73)** 26.389 (2.93)** -7.023 (0.99) -22.687 (1.84) -24.280 (2.07)* 14.670 (1.66) 4.909 (1.60) -1.697 (4.03)** -0.644 (1.80) 7.913 (3.45)** -5.500 (2.55)* stage_gdpgwr Constant H4 -0.011 (38.13)** -18.542 (2.24)* 13.078 (1.77) 11.041 (2.83)** 15.905 (2.13)* -0.266 (0.79) -0.294 (0.25) 4.708 (4.69)** 27.147 (3.02)** -7.026 (0.99) -22.213 (1.81) -23.532 (2.01)* 14.344 (1.63) 3.683 (1.20) -1.503 (3.68)** -0.655 (1.83) 8.227 (3.61)** -46.745 (0.92) -4343.27 1.52 (0.217) 75.99 [71.13 83.46] 0.16 -11.542 (3.69)** -6.352 (5.35)** 3.534 (0.07) -4329.98 28.10 (0.000)*** 75.99 [71.21 83.33] 0.16 -13.616 (0.26) -4340.81 6.45 (0.011)** 75.99 [71.14 83.44] 0.16 -3.330 (0.07) -4337.29 13.49 (0.000)*** 75.99 [71.17 83.4] 0.16 -8.561 (5.16)** 8.396 (0.17) -4330.93 26.20 (0.000)*** 75.99 [71.21 83.34] 0.16 Tables A6.13 Robustness check: substitute variable: population (continue) Bid price rep_gov water_problem will_service quality_deg age education income_level Income significant higher than need male Can see the river Far from the river d_fish Degree share2nd pop_density gdp_growth H1 -0.025 (34.88)** -0.226 (2.50)* 0.038 (0.48) 0.165 (3.95)** 0.233 (2.86)** -0.001 (0.39) 0.011 (0.85) 0.051 (4.63)** 0.300 (3.06)** -0.042 (0.54) -0.080 (0.59) -0.100 (0.78) 0.121 (1.27) 0.184 (5.46)** -0.001 (0.23) -0.027 (7.07)** -0.013 (0.53) Total_population H2 -0.025 (34.87)** -0.230 (2.55)* 0.097 (1.21) 0.123 (2.88)** 0.192 (2.35)* -0.001 (0.34) 0.013 (0.98) 0.057 (5.20)** 0.313 (3.19)** -0.055 (0.71) -0.041 (0.31) -0.048 (0.37) 0.155 (1.61) 0.164 (4.83)** -0.005 (1.07) -0.026 (6.55)** -0.023 (0.91) -0.015 (5.08)** H3 -0.025 (34.87)** -0.225 (2.49)* 0.099 (1.22) 0.130 (3.07)** 0.195 (2.39)* -0.001 (0.34) 0.014 (1.08) 0.058 (5.25)** 0.291 (2.97)** -0.054 (0.70) -0.060 (0.44) -0.071 (0.55) 0.154 (1.61) 0.195 (5.78)** -0.011 (2.34)* -0.021 (4.94)** -0.029 (1.16) -2.185 (4.70)** pop_pop H4 -0.025 (34.89)** -0.229 (2.54)* 0.045 (0.57) 0.127 (3.01)** 0.216 (2.66)** -0.002 (0.46) 0.005 (0.39) 0.055 (5.01)** 0.338 (3.43)** -0.081 (1.04) -0.055 (0.41) -0.099 (0.77) 0.129 (1.35) 0.177 (5.26)** -0.001 (0.18) -0.030 (7.72)** -0.059 (2.25)* Def Yes H4 -0.025 (34.86)** -0.252 (2.79)** 0.075 (0.94) 0.136 (3.18)** 0.245 (3.02)** -0.001 (0.21) 0.010 (0.81) 0.051 (4.66)** 0.307 (3.12)** -0.047 (0.60) -0.073 (0.54) -0.102 (0.80) 0.130 (1.37) 0.177 (5.24)** -0.007 (1.43) -0.029 (7.49)** -0.007 (0.29) -0.014 (5.42)** pop_gdppc Log likelihood LR Mean WTP KR CI Ratio H5 -0.025 (34.88)** -0.227 (2.51)* 0.080 (1.00) 0.125 (2.95)** 0.219 (2.70)** -0.001 (0.39) 0.009 (0.67) 0.057 (5.16)** 0.306 (3.12)** -0.064 (0.83) -0.064 (0.48) -0.092 (0.72) 0.143 (1.50) 0.207 (6.07)** -0.010 (2.25)* -0.023 (5.80)** -0.053 (2.06)* -0.009 (3.35)** -0.306 (0.58) -2184.3 27.21 [24.04 30.52] 0.24 0.274 (0.51) -2171.37 25.86 (0.000)*** 27.3 [25.32 30.43] 0.19 0.422 (0.77) -2173.25 22.1 (0.000)*** 27.29 [25.31 30.45] 0.19 0.792 (1.41) -2169.55 29.5 (0.014)** 27.26 [25.26 30.38] 0.19 H5 -0.025 (34.86)** -0.237 (2.63)** 0.095 (1.17) 0.128 (3.02)** 0.213 (2.62)** -0.001 (0.28) 0.013 (1.03) 0.057 (5.14)** 0.291 (2.96)** -0.054 (0.70) -0.065 (0.48) -0.086 (0.67) 0.153 (1.60) 0.193 (5.72)** -0.012 (2.39)* -0.024 (6.01)** -0.026 (1.03) H5 -0.025 (34.88)** -0.226 (2.50)* 0.038 (0.48) 0.165 (3.95)** 0.233 (2.86)** -0.001 (0.39) 0.011 (0.85) 0.051 (4.63)** 0.300 (3.06)** -0.042 (0.54) -0.080 (0.59) -0.100 (0.78) 0.121 (1.27) 0.184 (5.46)** -0.001 (0.23) -0.027 (7.07)** -0.013 (0.53) -3.111 (5.24)** pop_gdpgwr Constant H4 -0.025 (34.86)** -0.235 (2.61)** 0.098 (1.21) 0.123 (2.89)** 0.187 (2.29)* -0.001 (0.38) 0.014 (1.08) 0.059 (5.33)** 0.310 (3.16)** -0.060 (0.78) -0.046 (0.34) -0.054 (0.42) 0.162 (1.69) 0.168 (4.96)** -0.006 (1.41) -0.025 (6.43)** -0.034 (1.36) 0.147 (0.27) -2178.69 11.23 (0.217) 27.25 [25.21 30.41] 0.19 -2.461 (4.32)** -0.012 (5.10)** 0.469 (0.86) -2171.27 26.06 (0.000)*** 27.3 [25.32 30.43] 0.19 0.873 (1.53) -2170.57 27.48 (0.011)** 27.28 [25.29 30.41] 0.19 0.487 (0.88) -2174.99 18.63 (0.000)*** 27.28 [25.28 30.44] 0.19 -1.630 (4.47)** 0.464 (0.84) -2174.29 20.03 (0.000)*** 27.28 [25.29 30.44] 0.19 Tables A6.14 Robustness check: substitute variable: population (continue) Bid price rep_gov water_problem will_service quality_deg age education income_level Income significant higher than need male Can see the river Far from the river d_fish Degree share2nd pop_density gdp_growth H1 -0.016 (36.10)** -0.310 (3.45)** 0.027 (0.34) 0.169 (4.09)** 0.305 (3.77)** -0.003 (0.95) 0.002 (0.12) 0.039 (3.62)** 0.371 (3.79)** 0.026 (0.34) -0.163 (1.22) -0.191 (1.51) 0.180 (1.89) 0.137 (4.11)** -0.005 (1.21) -0.022 (5.59)** 0.057 (2.31)* Total_population H2 -0.017 (36.09)** -0.316 (3.51)** 0.088 (1.10) 0.127 (2.99)** 0.266 (3.27)** -0.003 (0.89) 0.003 (0.26) 0.046 (4.20)** 0.387 (3.95)** 0.013 (0.17) -0.123 (0.92) -0.140 (1.10) 0.215 (2.25)* 0.117 (3.49)** -0.009 (2.05)* -0.019 (5.04)** 0.049 (1.98)* -0.015 (5.20)** H3 -0.017 (36.09)** -0.311 (3.46)** 0.095 (1.18) 0.131 (3.11)** 0.266 (3.27)** -0.003 (0.89) 0.005 (0.38) 0.047 (4.32)** 0.365 (3.72)** 0.012 (0.16) -0.140 (1.05) -0.161 (1.27) 0.218 (2.28)* 0.150 (4.49)** -0.017 (3.46)** -0.014 (3.33)** 0.041 (1.66) -2.432 (5.25)** pop_pop H4 -0.017 (36.09)** -0.313 (3.48)** 0.032 (0.40) 0.146 (3.47)** 0.295 (3.64)** -0.004 (0.99) -0.002 (0.15) 0.042 (3.82)** 0.394 (4.01)** 0.002 (0.03) -0.146 (1.09) -0.190 (1.50) 0.185 (1.94) 0.132 (3.97)** -0.005 (1.18) -0.023 (5.96)** 0.030 (1.15) Prob Yes H4 -0.016 (36.10)** -0.313 (3.46)** 0.031 (0.38) 0.167 (3.92)** 0.306 (3.78)** -0.003 (0.94) 0.002 (0.12) 0.039 (3.63)** 0.372 (3.79)** 0.026 (0.34) -0.162 (1.21) -0.191 (1.51) 0.180 (1.89) 0.136 (4.08)** -0.006 (1.24) -0.022 (5.58)** 0.057 (2.32)* -0.008 (3.35)** pop_gdppc Log likelihood LR Mean WTP KR CI Ratio H5 -0.017 (36.09)** -0.312 (3.47)** 0.062 (0.78) 0.137 (3.24)** 0.295 (3.65)** -0.003 (0.95) -0.000 (0.02) 0.044 (4.03)** 0.378 (3.85)** 0.008 (0.10) -0.149 (1.12) -0.185 (1.46) 0.198 (2.08)* 0.155 (4.62)** -0.013 (2.77)** -0.018 (4.52)** 0.025 (0.99) -0.001 (0.30) -0.557 (1.07) -2202.27 52.68 [47.89 57.61] 0.18 0.005 (0.01) -2188.74 27.06 (0.000)*** 52.71 [49.65 57.39] 0.15 0.226 (0.42) -2188.47 27.6 (0.000)*** 52.7 [49.65 57.37] 0.15 0.100 (0.18) -2196.65 11.25 (0.014)** 52.68 [49.55 57.43] 0.15 H5 -0.017 (36.09)** -0.320 (3.56)** 0.077 (0.96) 0.137 (3.24)** 0.289 (3.56)** -0.003 (0.86) 0.003 (0.27) 0.044 (4.06)** 0.364 (3.72)** 0.015 (0.20) -0.149 (1.12) -0.180 (1.42) 0.207 (2.17)* 0.145 (4.34)** -0.015 (2.95)** -0.018 (4.64)** 0.047 (1.90) H5 -0.017 (36.09)** -0.314 (3.49)** 0.091 (1.14) 0.133 (3.16)** 0.263 (3.23)** -0.003 (0.92) 0.006 (0.44) 0.048 (4.40)** 0.362 (3.69)** 0.009 (0.12) -0.142 (1.07) -0.166 (1.31) 0.224 (2.34)* 0.150 (4.49)** -0.017 (3.51)** -0.014 (3.53)** 0.036 (1.46) -2.528 (4.30)** pop_gdpgwr Constant H4 -0.017 (36.08)** -0.322 (3.58)** 0.089 (1.11) 0.126 (2.99)** 0.261 (3.20)** -0.003 (0.94) 0.005 (0.36) 0.048 (4.34)** 0.384 (3.91)** 0.007 (0.09) -0.127 (0.95) -0.146 (1.15) 0.223 (2.33)* 0.121 (3.61)** -0.011 (2.40)* -0.019 (4.91)** 0.037 (1.49) -0.517 (0.96) -2202.23 0.09 (0.766) 52.68 [49.49 57.47] 0.15 -2.139 (3.78)** -0.013 (5.27)** 0.210 (0.39) -2188.39 27.77 (0.000)*** 52.7 [49.64 57.38] 0.15 0.380 (0.67) -2193.02 18.51 (0.000)** 52.69 [49.61 57.39] 0.15 0.117 (0.21) -2195.13 14.29 (0.000)*** 52.69 [49.59 57.41] 0.15 -1.860 (5.12)** 0.294 (0.54) -2189.15 26.25 (0.000)*** 52.7 [49.64 57.37] 0.15 Tables A6.15 Robustness check: substitute variable: population (continue) Bid price rep_gov water_problem will_service quality_deg age education income_level Income significant higher than need male Can see the river Far from the river d_fish Degree share2nd pop_density gdp_growth H1 -0.009 (36.11)** -0.126 (1.41) 0.067 (0.86) 0.167 (4.04)** 0.222 (2.76)** -0.003 (0.73) -0.003 (0.27) 0.036 (3.28)** 0.291 (2.99)** -0.054 (0.70) -0.325 (2.43)* -0.395 (3.11)** 0.057 (0.60) 0.049 (1.49) -0.011 (2.71)** -0.009 (2.30)* 0.117 (4.74)** Total_population H2 -0.009 (36.11)** -0.127 (1.42) 0.116 (1.45) 0.133 (3.15)** 0.190 (2.34)* -0.002 (0.67) -0.002 (0.16) 0.040 (3.71)** 0.302 (3.09)** -0.065 (0.84) -0.296 (2.21)* -0.357 (2.80)** 0.082 (0.86) 0.032 (0.96) -0.014 (3.36)** -0.007 (1.80) 0.111 (4.50)** -0.012 (4.13)** H3 -0.009 (36.11)** -0.123 (1.38) 0.130 (1.63) 0.132 (3.13)** 0.185 (2.28)* -0.002 (0.67) -0.001 (0.04) 0.043 (3.91)** 0.284 (2.90)** -0.068 (0.88) -0.308 (2.31)* -0.372 (2.92)** 0.089 (0.93) 0.059 (1.80) -0.022 (4.61)** -0.001 (0.32) 0.103 (4.16)** -2.236 (4.85)** pop_pop H4 -0.009 (36.11)** -0.126 (1.41) 0.070 (0.89) 0.150 (3.58)** 0.215 (2.67)** -0.003 (0.75) -0.006 (0.46) 0.037 (3.41)** 0.307 (3.13)** -0.071 (0.92) -0.314 (2.35)* -0.395 (3.11)** 0.059 (0.62) 0.045 (1.37) -0.011 (2.69)** -0.010 (2.55)* 0.098 (3.78)** Not Sure H4 -0.009 (36.11)** -0.128 (1.43) 0.071 (0.89) 0.165 (3.88)** 0.223 (2.77)** -0.003 (0.72) -0.003 (0.27) 0.036 (3.28)** 0.292 (2.99)** -0.054 (0.71) -0.324 (2.43)* -0.395 (3.11)** 0.057 (0.60) 0.049 (1.47) -0.012 (2.63)** -0.009 (2.32)* 0.117 (4.75)** -0.006 (2.37)* pop_gdppc Log likelihood LR Mean WTP KR CI Ratio H5 -0.009 (36.11)** -0.125 (1.40) 0.096 (1.21) 0.140 (3.32)** 0.213 (2.65)** -0.003 (0.72) -0.005 (0.39) 0.039 (3.60)** 0.296 (3.03)** -0.070 (0.91) -0.315 (2.36)* -0.392 (3.09)** 0.070 (0.73) 0.063 (1.90) -0.018 (3.88)** -0.006 (1.41) 0.091 (3.55)** -0.001 (0.28) -0.749 (1.44) -2312 92.56 [83.87 101.56] 0.19 -0.305 (0.58) -2303.46 17.08 (0.000)*** 92.58 [86.97 101.12] 0.15 -0.034 (0.06) -2300.26 23.49 (0.000)*** 92.58 [86.98 101.1] 0.15 -0.287 (0.52) -2309.2 5.6 (0.018)** 92.56 [86.9 101.16] 0.15 H5 -0.009 (36.10)** -0.134 (1.50) 0.120 (1.49) 0.134 (3.17)** 0.205 (2.54)* -0.002 (0.63) -0.002 (0.12) 0.041 (3.73)** 0.284 (2.91)** -0.066 (0.86) -0.314 (2.35)* -0.387 (3.04)** 0.083 (0.88) 0.056 (1.71) -0.021 (4.32)** -0.005 (1.34) 0.107 (4.33)** H5 -0.009 (36.11)** -0.126 (1.41) 0.067 (0.86) 0.167 (4.04)** 0.222 (2.76)** -0.003 (0.73) -0.003 (0.27) 0.036 (3.28)** 0.291 (2.99)** -0.054 (0.70) -0.325 (2.43)* -0.395 (3.11)** 0.057 (0.60) 0.049 (1.49) -0.011 (2.71)** -0.009 (2.30)* 0.117 (4.74)** -2.096 (3.59)** pop_gdpgwr Constant H4 -0.009 (36.10)** -0.132 (1.48) 0.123 (1.54) 0.128 (3.04)** 0.181 (2.24)* -0.003 (0.71) -0.001 (0.06) 0.043 (3.91)** 0.301 (3.08)** -0.072 (0.94) -0.297 (2.22)* -0.358 (2.81)** 0.092 (0.97) 0.033 (1.00) -0.016 (3.74)** -0.006 (1.63) 0.100 (4.02)** -0.712 (1.33) -2311.96 0.08 (0.779) 92.56 [86.8 101.2] 0.16 -2.215 (3.92)** -0.011 (4.72)** -0.066 (0.12) -2300.84 22.32 (0.000)*** 92.57 [86.99 101.09] 0.15 0.027 (0.05) -2305.57 12.86 (0.011)** 92.57 [86.93 101.14] 0.15 -0.055 (0.10) -2304.3 15.4 (0.000)*** 92.56 [86.91 101.12] 0.15 -1.865 (5.15)** 0.099 (0.18) -2298.74 26.51 (0.000)*** 92.57 [86.99 101.07] 0.15 Tables A6.16 Robustness check: substitute variable: population (continue) Bid price rep_gov water_problem will_service quality_deg age education income_level Income significant higher than need male Can see the river Far from the river d_fish Degree share2nd pop_density gdp_growth H1 -0.011 (38.13)** -18.436 (2.19)* 7.080 (0.95) 15.093 (3.87)** 20.245 (2.67)** -0.271 (0.79) -0.554 (0.46) 4.019 (3.96)** 27.176 (2.96)** -5.829 (0.81) -25.250 (2.02)* -28.295 (2.38)* 10.770 (1.20) 5.134 (1.65) -0.917 (2.29)* -1.011 (2.83)** 9.605 (4.16)** Total_population H2 -0.011 (38.13)** -18.309 (2.20)* 11.967 (1.61) 11.441 (2.91)** 16.625 (2.21)* -0.248 (0.73) -0.421 (0.35) 4.475 (4.44)** 27.850 (3.08)** -6.868 (0.96) -22.002 (1.78) -23.977 (2.04)* 13.295 (1.50) 3.276 (1.06) -1.200 (3.00)** -0.811 (2.28)* 8.853 (3.88)** -1.177 (4.50)** H3 -0.011 (38.13)** -17.863 (2.16)* 13.057 (1.76) 11.481 (2.94)** 16.239 (2.17)* -0.246 (0.73) -0.279 (0.23) 4.654 (4.62)** 25.907 (2.87)** -7.071 (0.99) -23.194 (1.88) -25.467 (2.17)* 13.718 (1.55) 5.971 (1.95) -1.896 (4.31)** -0.287 (0.76) 8.127 (3.55)** -213.065 (5.00)** pop_pop H4 -0.011 (38.13)** -18.371 (2.19)* 7.382 (1.00) 13.414 (3.40)** 19.430 (2.57)* -0.278 (0.82) -0.798 (0.66) 4.151 (4.10)** 28.503 (3.11)** -7.457 (1.03) -24.105 (1.93) -28.118 (2.37)* 10.969 (1.23) 4.725 (1.52) -0.903 (2.26)* -1.104 (3.08)** 7.744 (3.19)** -0.565 (2.43)* pop_gdppc Wang and HE H4 -0.011 (38.13)** -18.420 (2.18)* 7.057 (0.94) 15.112 (3.79)** 20.234 (2.67)** -0.272 (0.79) -0.554 (0.46) 4.019 (3.96)** 27.173 (2.96)** -5.827 (0.81) -25.254 (2.02)* -28.290 (2.38)* 10.768 (1.20) 5.137 (1.65) -0.913 (2.13)* -1.010 (2.79)** 9.601 (4.14)** 0.006 (0.02) pop_gdpgwr Constant Log likelihood LR Mean WTP KR CI Ratio -62.418 (1.27) -4344.03 75.99 [71.19 83.37] 0.2 -16.358 (0.33) -4334.06 19.95 (0.000)*** 75.99 [71.2 83.35] 0.16 6.984 (0.14) -4331.72 24.62 (0.000)*** 75.99 [71.14 83.44] 0.16 -17.693 (0.34) -4341.09 5.88 (0.015)** 75.99 [71.12 83.47] 0.16 -62.681 (1.24) -4344.03 0 (0.982) 75.99 [71.2 83.35] 0.16 H4 -0.011 (38.13)** -18.785 (2.27)* 12.442 (1.68) 11.085 (2.83)** 15.856 (2.11)* -0.261 (0.77) -0.299 (0.25) 4.669 (4.63)** 27.591 (3.06)** -7.486 (1.05) -22.120 (1.79) -24.120 (2.05)* 14.170 (1.60) 3.446 (1.12) -1.368 (3.38)** -0.754 (2.12)* 7.783 (3.38)** H5 -0.011 (38.13)** -18.143 (2.17)* 9.832 (1.33) 12.354 (3.14)** 19.137 (2.55)* -0.266 (0.78) -0.709 (0.59) 4.343 (4.30)** 27.275 (3.00)** -7.309 (1.02) -24.141 (1.94) -27.681 (2.35)* 11.983 (1.35) 6.364 (2.05)* -1.507 (3.52)** -0.694 (1.90) 7.073 (2.96)** H5 -0.008 (23.57)** -0.239 (2.38)* 0.004 (0.04) 0.347 (7.35)** 0.223 (2.42)* -0.003 (0.66) -0.007 (0.50) 0.060 (5.04)** 0.218 (1.96)* -0.057 (0.65) -0.224 (1.43) -0.119 (0.80) 0.177 (1.65) 0.143 (3.97)** -0.009 (1.53) -0.001 (0.15) -0.022 (0.80) H5 -0.008 (23.37)** -0.236 (2.34)* -0.014 (0.15) 0.355 (7.57)** 0.235 (2.55)* -0.003 (0.65) -0.009 (0.70) 0.059 (4.98)** 0.202 (1.82) -0.060 (0.69) -0.239 (1.53) -0.169 (1.17) 0.187 (1.76) 0.137 (3.85)** -0.004 (0.89) -0.002 (0.48) -0.019 (0.70) -199.340 (3.66)** -1.107 (4.98)** 5.330 (0.11) -4331.85 24.36 (0.000)*** 75.99 [71.17 83.4] 0.16 -238.695 (3.71)** 11.867 (0.23) -4337.41 13.24 (0.000)*** 75.99 [71.17 83.4] 0.16 0.125 (0.00) -4337.2 13.67 (0.000)*** 75.99 [71.21 83.33] 0.16 -174.520 (5.23)** 18.174 (0.36) -4330.6 26.86 (0.000)*** 75.99 [71.21 83.34] 0.16 Tables A6.17 Robustness check: substitute variable: population (continue) Bid price rep_gov water_problem will_service quality_deg age education income_level Income significant higher than need male Can see the river Far from the river d_fish Degree share2nd pop_density gdp_growth H1 -0.005 (13.01)** -0.265 (2.37)* 0.087 (0.84) 0.352 (6.69)** 0.370 (3.60)** -0.002 (0.40) 0.000 (0.02) 0.055 (4.09)** 0.187 (1.49) 0.031 (0.32) -0.079 (0.45) -0.020 (0.12) 0.174 (1.47) 0.137 (3.45)** -0.003 (0.58) -0.002 (0.38) -0.017 (0.54) Total_population H2 -0.005 (13.03)** -0.274 (2.45)* 0.100 (0.97) 0.333 (6.25)** 0.359 (3.49)** -0.002 (0.48) 0.007 (0.48) 0.056 (4.16)** 0.207 (1.64) 0.022 (0.23) -0.046 (0.26) 0.051 (0.30) 0.158 (1.32) 0.128 (3.18)** -0.004 (0.74) -0.001 (0.25) -0.023 (0.73) -0.008 (2.11)* H3 -0.005 (13.02)** -0.272 (2.43)* 0.106 (1.02) 0.336 (6.33)** 0.347 (3.35)** -0.002 (0.42) 0.005 (0.35) 0.057 (4.19)** 0.213 (1.69) 0.028 (0.29) -0.046 (0.26) 0.059 (0.35) 0.153 (1.29) 0.147 (3.63)** -0.008 (1.34) 0.002 (0.36) -0.024 (0.78) -1.315 (2.07)* pop_pop H4 -0.005 (13.04)** -0.281 (2.49)* 0.084 (0.81) 0.341 (6.42)** 0.366 (3.56)** -0.002 (0.47) 0.003 (0.21) 0.055 (4.12)** 0.191 (1.52) 0.024 (0.24) -0.058 (0.33) 0.001 (0.01) 0.165 (1.39) 0.138 (3.44)** -0.003 (0.56) -0.003 (0.60) -0.027 (0.84) Single Bound H4 -0.005 (13.01)** -0.267 (2.38)* 0.093 (0.89) 0.350 (6.65)** 0.373 (3.62)** -0.002 (0.41) 0.000 (0.03) 0.055 (4.08)** 0.191 (1.52) 0.033 (0.34) -0.078 (0.44) -0.015 (0.09) 0.174 (1.47) 0.136 (3.39)** -0.004 (0.70) -0.002 (0.45) -0.015 (0.48) -0.004 (1.22) pop_gdppc Log likelihood LR Mean WTP KR CI Ratio H5 -0.005 (13.05)** -0.286 (2.55)* 0.101 (0.97) 0.334 (6.29)** 0.351 (3.40)** -0.002 (0.44) 0.004 (0.31) 0.056 (4.16)** 0.208 (1.65) 0.024 (0.25) -0.038 (0.22) 0.047 (0.29) 0.154 (1.29) 0.153 (3.73)** -0.007 (1.26) -0.000 (0.02) -0.034 (1.08) -0.002 (0.46) -1.130 (1.73) -457.41 134.23 [113.95 0.29 152.41] -0.931 (1.41) -455.19 4.45 (0.035)** 134.48 [121.52 0.25 155.05] -0.839 (1.26) -455.26 4.3 (0.038)** 134.61 [121.63 155.12] 0.25 -0.920 (1.36) -456.67 1.48 (0.224) 134.45 [121.44 0.25 155.1] H5 -0.005 (13.01)** -0.270 (2.41)* 0.110 (1.06) 0.341 (6.44)** 0.358 (3.48)** -0.002 (0.42) 0.003 (0.22) 0.056 (4.14)** 0.212 (1.68) 0.034 (0.35) -0.059 (0.34) 0.037 (0.22) 0.162 (1.36) 0.144 (3.57)** -0.009 (1.38) -0.000 (0.02) -0.020 (0.65) H5 -0.005 (13.00)** -0.270 (2.41)* 0.104 (1.00) 0.337 (6.36)** 0.343 (3.31)** -0.002 (0.43) 0.005 (0.34) 0.057 (4.20)** 0.213 (1.69) 0.029 (0.30) -0.049 (0.28) 0.055 (0.33) 0.156 (1.31) 0.147 (3.62)** -0.009 (1.38) 0.002 (0.31) -0.026 (0.84) -1.675 (2.19)* pop_gdpgwr Constant H4 -0.005 (13.01)** -0.274 (2.44)* 0.097 (0.94) 0.335 (6.29)** 0.353 (3.42)** -0.002 (0.50) 0.007 (0.45) 0.057 (4.17)** 0.207 (1.64) 0.025 (0.26) -0.050 (0.28) 0.045 (0.27) 0.160 (1.34) 0.130 (3.23)** -0.005 (0.84) -0.001 (0.20) -0.027 (0.87) -1.088 (1.65) -457.31 0.21 (0.649) 134.2 [120.67 154.73] 0.25 -1.731 (1.86) -0.006 (2.00)* -0.851 (1.27) -455.4 4.02 (0.045)** 134.51 [121.6 155.11] 0.25 -0.683 (1.00) -454.99 4.84 (0.028)** 134.81 [121.87 155.31] 0.25 -0.827 (1.23) -455.67 3.48 (0.062)* 134.47 [121.32 154.93] 0.25 -1.016 (2.04)* -0.800 (1.19) -455.34 4.15 (0.042)** 134.62 [121.65 155.15] 0.25 Tables A6.18 Robustness check: substitute variable: population (continue) Bid price rep_gov water_problem will_service quality_deg age education income_level Income significant higher than need male Can see the river Far from the river d_fish Degree share2nd pop_density gdp_growth H1 -0.008 (23.48)** -0.236 (2.34)* -0.014 (0.15) 0.355 (7.57)** 0.235 (2.55)* -0.003 (0.65) -0.009 (0.70) 0.059 (4.98)** 0.202 (1.82) -0.060 (0.69) -0.239 (1.53) -0.169 (1.17) 0.187 (1.76) 0.137 (3.85)** -0.004 (0.89) -0.002 (0.48) -0.019 (0.70) Total_population H2 -0.008 (23.28)** -0.241 (2.39)* -0.007 (0.08) 0.343 (7.20)** 0.226 (2.45)* -0.003 (0.71) -0.005 (0.36) 0.060 (5.04)** 0.214 (1.93) -0.065 (0.74) -0.219 (1.39) -0.119 (0.80) 0.179 (1.67) 0.131 (3.65)** -0.005 (1.00) -0.002 (0.37) -0.023 (0.83) -0.005 (1.51) H3 -0.008 (23.40)** -0.239 (2.38)* -0.001 (0.01) 0.344 (7.25)** 0.216 (2.33)* -0.003 (0.66) -0.005 (0.41) 0.061 (5.06)** 0.219 (1.97)* -0.062 (0.71) -0.216 (1.38) -0.107 (0.72) 0.173 (1.62) 0.144 (4.00)** -0.008 (1.47) 0.001 (0.15) -0.025 (0.89) -0.963 (1.67) pop_pop H4 -0.008 (23.57)** -0.241 (2.39)* -0.015 (0.16) 0.350 (7.37)** 0.233 (2.52)* -0.003 (0.68) -0.008 (0.60) 0.060 (5.00)** 0.202 (1.83) -0.063 (0.72) -0.232 (1.48) -0.160 (1.09) 0.184 (1.72) 0.138 (3.85)** -0.004 (0.88) -0.003 (0.57) -0.023 (0.81) -0.001 (0.55) pop_gdppc Double Bound H4 -0.008 (23.65)** -0.237 (2.36)* -0.009 (0.09) 0.354 (7.53)** 0.237 (2.57)* -0.003 (0.65) -0.009 (0.68) 0.059 (4.98)** 0.204 (1.85) -0.057 (0.65) -0.238 (1.53) -0.162 (1.11) 0.186 (1.75) 0.136 (3.78)** -0.005 (0.99) -0.002 (0.54) -0.018 (0.63) -0.002 (0.48) pop_gdpgwr Constant Log likelihood LR Mean WTP KR CI Ratio -0.516 (0.89) -1045.41 103.43 [91.57 114.44] 0.22 -0.389 (0.67) -1044.26 2.29 (0.131) 103.51 [95.68 115.01] 0.19 -0.312 (0.53) -1044.01 2.79 (0.095)* 103.55 [95.47 114.94] 0.19 -0.431 (0.72) -1045.25 0.3 (0.581) 103.47 [95.7 115] 0.19 -0.477 (0.82) -1045.29 0.23 (0.63) 103.37 [95.15 114.63] 0.19 H4 -0.008 (23.21)** -0.241 (2.40)* -0.009 (0.09) 0.344 (7.23)** 0.222 (2.40)* -0.003 (0.72) -0.005 (0.38) 0.061 (5.05)** 0.214 (1.93) -0.064 (0.73) -0.221 (1.41) -0.121 (0.82) 0.179 (1.68) 0.133 (3.69)** -0.005 (1.07) -0.002 (0.34) -0.026 (0.93) H5 -0.008 (23.31)** -0.248 (2.46)* -0.005 (0.05) 0.343 (7.23)** 0.220 (2.38)* -0.003 (0.68) -0.006 (0.47) 0.060 (5.04)** 0.214 (1.93) -0.064 (0.73) -0.214 (1.36) -0.120 (0.81) 0.174 (1.62) 0.148 (4.05)** -0.007 (1.38) -0.001 (0.19) -0.031 (1.07) -1.132 (1.62) -0.004 (1.45) -0.336 (0.57) -1044.36 2.1 (0.147) 103.51 [95.68 115.01] 0.19 -0.226 (0.37) -1044.09 2.64 (0. 104) 103.55 [95.47 114.94] 0.19 H5 -0.008 (23.57)** -0.239 (2.38)* 0.004 (0.04) 0.347 (7.35)** 0.223 (2.42)* -0.003 (0.66) -0.007 (0.50) 0.060 (5.04)** 0.218 (1.96)* -0.057 (0.65) -0.224 (1.43) -0.119 (0.80) 0.177 (1.65) 0.143 (3.97)** -0.009 (1.53) -0.001 (0.15) -0.022 (0.80) -1.364 (1.61) -0.289 (0.49) -1044.11 2.58 (0.107) 103.47 [95.7 115] 0.19 H5 -0.008 (23.37)** -0.236 (2.34)* -0.014 (0.15) 0.355 (7.57)** 0.235 (2.55)* -0.003 (0.65) -0.009 (0.70) 0.059 (4.98)** 0.202 (1.82) -0.060 (0.69) -0.239 (1.53) -0.169 (1.17) 0.187 (1.76) 0.137 (3.85)** -0.004 (0.89) -0.002 (0.48) -0.019 (0.70) -0.754 (1.66) -0.279 (0.47) -1044.02 2.77 (0.009)* 103.37 [95.15 114.63] 0.19