The methodologies of economic evaluation III You pay nothing if u ask ... And give an answer? 1. THE METHOD OF THE CONTINGENT EVALUATION 2. INTERPRETATION OF THE RESULTS 3. PROBLEMS OF APPLICATION Expression method of the preference THE METHOD OF THE CONTINGENT EVALUATION The revelation methods of the preferences base the evaluation on the observation of the individuals behavior according to the conditions of choice particularly, the real and ‘indirect’ market prices The expression methods of the preferences ask directly the individuals to evaluate in opportune conditions a determined environmental property The method of the contingent evaluation is based on -direct, telephone, postal interviewwith the property users. The users can be individualized according to their frequency for environmental property to be appraised... … That on the base of another characteristic for instance residence in the commune in which the property is found The contingent evaluation is not confined to consider the real use, and therefore to measure the value of direct or indirect use. It can also concern the potential use value of option and even the distinguished interest from value of existence use The contingent evaluation generally consists in the revelation of availability to pay (DAP) for safeguarding (or for the production, or for the restoration, etc.) of a determined environmental property on a representative sample of the users - recent or potential -. On the base of the samples data it becomes possible to calculate the average availability to pay that can be extrapolated to the whole population multiplying such value by the total number of the users. So we obtain an estimation of the total value assigned to the environmental property from the concerned population. A possible application of the method can propose to the users different sceneries where they considered levels of safeguarding -production, restoration- property alternatives, distinguishing particularly between users and non users. We are able to obtain a detailed estimation of the curves of question observing how the availability to pay changes for the different levels of property endowment determining then the average curve of question and that total for the whole population. In general, the individuals manifest a certain availability to pay for an ‘essential’ level of property endowment, while availability is progressively grown weak for ulterior increases of the endowment level. The curves of reconstructed question are therefore tilted negatively. Besides, availability to pay of some users is generally superior to that of the non users. Positive availability to pay of the non users is an index of value of option and/or value of existence and it can be also the signal of an altruistic predisposition. Any of these aspects can be noticed through methodologies that trust entirely individuals choices of market! This is true and great reason for those natural resources, for those who don’t have natural resources and for those who don’t have sense to speak of value of use but that can be thought very important and of big value... … Think of the Anta tide or the Amazonian forests! The contingent evaluation can furnish a base for any type of cost-benefit analysis that has an environmental impact, requiring only that the individuals interested have enough information to be able to manifest their own availability to pay. It is possible to perform a contingent evaluation - in terms of availability - to accept a compensation in front of missing production of a benefit… ... Or to the production of a damage in terms of available environmental resources. PROBLEMS Overestimate of availability to pay Relationship between availability to pay and to accept Relationship between ‘parts’ and ‘all’ Payment methods Initial offer DAP OVERESTIMATION The method of the contingent evaluation is based on the hypothesis that the individual is able to appraise correctly his availability to pay so as they can prepare a determined benefit. The application of payment represent a hypothetical situation: how they can be sure that the individuals are indeed prepared to pay the declared sums? And if it was not, what meaning such declarations of availability would have? The available experiments show that when the individual is asked to pay the sums, the real payments are around 70-90 % of the declared sums. If from one side the real availability to pay is underestimated the paid percentage results to be superior to those that many researchers had foreseen.. DAP and DAA As being said ,the availability to pay for a benefit and availability to accept a compensation for a damage should be equivalent formulations that achieve the same results from the point of view of the evaluation of the resource. The “price” that will be paid for having it should be equal to the compensation required for not having it. The empirical studies show that the DAA overcomes highly the DAP This shows that the individuals are not reliable in their evaluations! Also it is discovered that this anomaly is largely explained from the cognitive mechanisms that govern the human decisions… ... For the production of a damage - the worse of the recent situation has a superior weight in comparison to missing production of a benefit - missing improvement of the recent situation - … .... Explain the discrepancy between the two measures. On the other hand we must take care that the questions on the DAP and those based on the DAA require from the individuals mental calculations of enough complex evaluation that not all has the patience or the desire to do! It is necessary therefore to recognize that at least the discrepancy between the two evaluations could reflect some inaccurate answers The “Part” and the “All” It is noticed that if the individuals are asked about the DAP for the safeguarding of a resource for instance, a lake that takes part of a wide resource for instance, a lake region. The evaluation performed for ‘partial’ property (the single lake) results very similar to those of ‘total’ property (the whole lake region). … It is Rather strange like criterion of evaluation! The individuals tend to organize their budget by categories, and therefore if the amount once increased over the budget it will affect the ability to buy something else! The problem can be surrounded - Remember the individuals that they can be called to appraise more environmental property, and for each of them it must be determined the DAP - Choosing only groups of wide environmental property to be appraised... … Always underlining that this is performed on the base of the proper income, whose amount is well precise value to be limited! But the individuals are able to appraise whole wide and complex property as a whole lake region? And how much does their evaluation reflect their own preferences and how the desire of “well to show up” to their eyes and of the interviewer? PAYMENT TOOLS The formulation of the evaluation questions should refer to a specific payment tool, to make the question more “concrete” ... … And to avoid the problem of different answers regarding the mean of payment. The DAP of many individuals is for example high if the payment is done through taxes rather than through a direct contribution! The better rule is to choose the payment mean that would be presumably selected from the majority of the individuals. INITIAL OFFER In some cases, in the direct interviews, the DAP is determined from an initial payment application for a precise sum that varied up to determine the exact sum that the individual is prepared to pay. Yet, the result seems to depend substantially on the amount of the initial application! This is a serious problem for which a satisfactory solution is not found till now.