& Deciphering the Relationship between Structural Change and Urbanization in Africa Analyse de la Relation entre Transformation Structurelle et Urbanisation en Afrique Louis de Berquin E YIKE M BONGO University of Dschang Laboratoire d’Économie et Géographie des Transports eyike76@gmail.com/louis.eyike@univ-dschang.org ORCID : 0000-0001-9910-8705 Auteur correspondant Alexandre Turpin I ROUME A B OUEBE University of Douala Laboratoire d’Économie et Géographie des Transports doniroume@yahoo.fr ORCID : 0009-0001-2051-1264 Linda T IAGUE Z ANFACK University of Dschang zanfacktiaguel@yahoo.com ORCID : 0000-0002-2950-3336 Mots clés : gouvernance, ressources naturelles, transformation structurelle, urbanisation. Keywords : governance, natural resource, structural change, urbanization. Classification JEL : L16, R12, R23 rticle on line 2025 - N° 1 - pp. 25-51 Revue d’Économie Régionale & Urbaine 25 Deciphering the Relationship between Structural Change and Urbanization in Africa Résumé Le lien entre l’urbanisation et la croissance économique dans les économies en développement reste difficile à cerner, en raison de facteurs tels que l’abondance des ressources naturelles et les niveaux élevés de pauvreté qui incitent à l’exode rural en quête de meilleures opportunités. Reconnaissant que la transformation structurelle est un élément clé de la croissance économique, cette étude examine le lien entre le changement structurel et l’urbanisation dans 53 pays africains entre 2010 et 2020. En utilisant la méthode des moments généralisés (GMM), des estimateurs de variables instrumentales (IV) et des techniques de régression par quantile, notre recherche met en évidence une relation positive constante entre les changements structurels et l’urbanisation. La démocratie semble avoir un impact négatif sur les taux d’urbanisation. La présence de ressources naturelles, en particulier de pétrole, influe sur la nature des changements structurels et de l’urbanisation. Abstract The nexus between urbanization and economic growth in developing economies, particularly in Africa, remains elusive, attributed to factors such as abundant natural resources driving growth dynamics and high poverty levels prompting rural-urban migration for better opportunities, posing a paradox yet to be fully grasped. Recognizing that structural transformation is a key component of economic growth, this study examines the link between structural change and urbanization across 53 African nations from 2010 to 2020. Using the Generalized Method of Moments (GMM), instrumental variables (IV) estimators, and quantile regression techniques, our research uncovers a consistently positive relationship between structural change and urbanization. However, the analysis also indicates a troubling positive correlation with corruption. In contrast, democracy seems to have a negative impact on urbanization rates. The presence of natural resources, particularly oil, is found to affect the nature of structural change and urbanization. The findings of this study have several implications for policymakers in Africa. Firstly, fostering structural transformation, particularly through industrialization, should be a key priority for promoting urbanization and economic development. Policies aimed at promoting economic growth and reducing corruption are crucial for fostering sustainable urbanization. Moreover, careful management of natural resource wealth is essential to avoid the adverse effects of the "resource curse" on urban development. Points clés – Nous analysons l’impact de la transformation structurelle sur le processus d’urbanisation en Afrique. – La transformation structurelle est positivement corrélée à l’urbanisation en Afrique. – Les ressources naturelles modifient le sens de la relation entre transformation structurelle et urbanisation en Afrique. 26 L. de B. E YIKE M BONGO , A. T. I ROUME A B OUEBE , L. T IAGUE Z ANFACK -1Introduction Urbanization and economic growth appear to be very closely correlated, so that urbanization is often used as a proxy for growth. While some studies present urbanization as dependent on economic progress (Michaels et al., 2012; Gollin et al., 2016), recent studies highlight the existence of an urban dividend (Brunt and GarcíaPeñalosa, 2021). This dividend involves access to basic infrastructure and education for urban populations. However, in the context of developing economies in general, and in the case of Africa in particular, the correlation between urbanization and economic growth appears weak (Henderson and Kriticos, 2018; Diao et al., 2019). The reasons for this "paradox" are not yet well understood. Firstly, Africa’s abundance of natural resources helps to explain the growth dynamic, while the high level of poverty may explain the migration from rural areas to cities in search of a better situation. According to forecasts by the Economic Commission for Africa, more than half of Africa’s population will live in urban areas by 2035 (ECA, 2022), and more than 90% of the world’s urban population growth will occur in Africa. This sharp rise in the pace of urbanization is associated with renewed growth, reviving hopes of an association between urbanization and economic expansion (Rodrik et al., 2014). In the same vein, structural transformation appears to be a prerequisite for economic growth. According to the African Development Bank, structural transformation is consubstantial to Africa’s economic development (AfDB, 2018). Structural transformation refers to the progressive reallocation of factors of production from low-productivity sectors to more productive sectors (Klinger and Lederman, 2004; Avom and Nguekeng, 2020). However, there is no universally accepted measure of structural change. For some economists, stuctural change can be measured by industrialization (Nguimkeu and Zeufack, 2019; AfDB, 2018; Van Neuss, 2019; Lectard, 2017), while others measure it by diversification and/or economic complexity (Cadot et al., 2011; Hidalgo and Haussmann, 2009). Equating it with industrialization, the African Development Bank shows that between 1995 and 2018, the share of the primary sector in African GDP fell from almost 40% to 31%, while the shares of the secondary and tertiary sectors rose respectively from 23% to 26% and from 36% to 41%. This evolution is consistent with the structural transformation process (AfDB, 2018). There is an abundant literature on the correlations between urbanization and growth (Glaeser, 2014; Rodrik, 2016; Henderson and Kriticos, 2018; Diao et al., 2019, 2021; McMillan and Zeufack, 2022) on the one hand, and structural transformation and growth (Nguimkeu and Zeufack, 2019; AfDB, 2018; Van Neuss, 2019; Lectard, 2017) on the other. However, the literature on the role that structural transformation can play in explaining urbanization dynamics is fairly recent (Gollin et al., 2016; Metha, 2018; Peng et al., 2023; Brunt and García-Peñalosa, 2022; Abbas et al., 2023; Cœurdacier et al., 2022). By way of illustration, Michaels et al. (2012) show that the urbanization of America between 1880 and 2000 is the result of the change in the 2025 - N° 1 Revue d’Économie Régionale & Urbaine 27 Deciphering the Relationship between Structural Change and Urbanization in Africa structure of employment between the agricultural and industrial sectors. Moreover, literature on the specific context of Africa is almost non-existent. In this sense, Gollin et al. (2016) analyze the effect of natural resource abundance on urbanization and conclude that the correlation between urbanization and industrialization is not robust in the specific case of Africa. The main question addressed in this paper is: by which transmission channels structural transformation affects urbanization in African context? We postulate that African urbanization can be explained by structural transformation via two main channels. Firstly, jobs in the formal sector, excluding the civil service, are virtually all concentrated in urban areas. This contributes to the migration of people from rural to urban areas. In addition, as industrialization improves infrastructure and living conditions in urban areas, it helps to attract rural populations to the cities in search of higher living standards. This paper makes a twofold contribution to the existing literature. Firstly, it is one of the few empirical studies on the link between structural change and urbanization focusing specifically on the African context. Secondly, this study analyzes the impact of natural resource abundance on the relationship between urbanization and structural change. In addition to this introduction, the paper is organized around three sections. Section 2 presents the data and the methodological approach used. Section 3 discusses the results, and the final section is devoted to the conclusion and policy implications of the results. -2Literature review There is an abundance of theoretical and empirical literature on the causes and consequences of urbanization, particularly in developing countries. Among the works devoted to the explanatory factors of urbanization, the literature focuses on the socio-economic causes, while with regard to its consequences, a significant part of this literature analyzes the impact of urbanization on growth. 2.1. The urbanization-development nexus A large body of literature is devoted to the study of the relationship between urbanization and growth. There is no consensus on this relationship. For some, the emergence of cities can promote economic growth through the industrialization channel by increasing the market size, favoring emergence of a specialized workforce and knowledge spillovers (Quigley, 2009). Moreover, this relationship depends of productivity growth which is associated with the increasing size of the metropolis and the emergence of economies of scale due to the presence of large companies (OECD, 2016). 28 L. de B. E YIKE M BONGO , A. T. I ROUME A B OUEBE , L. T IAGUE Z ANFACK The theory of “districts” asserted that cities are innovative places conducive to growth (Marshall, 1890). As a result, urbanization favors local scale effects and facilitates knowledge transfer, increasing industrial specialization, leading to reduced transaction costs, increased wealth and reduced poverty (Olsson, 2009). Empirically, pioneer studies carried out on the urbanization-development nexus support that economic growth and structural transformation (the shift from agriculture to industry) are accompanied not only by an increase in the rate of urbanization, but also by an increase in metropolitan concentration (Kuznets, 1955; Williamson, 1965). Some studies focus on the impact of development on urban inequalities. For example, Williamson (1965) argues the existence of an inverted-U curve between economic growth and urban inequality. In the first stage of development, economic growth is associated with an increase in urban inequalities. Above a certain threshold, development reduces urban inequalities. On the same vein, Krugman (1991) shows that increased urbanization affects economic development and favors inequalities in their early stages. Recent empirical studies have been carried out to analyze urbanization-growth nexus (Ngounou et al., 2023; Pradhan et al., 2021; Leitão, 2013; Nguyen, 2018; Jiang et al., 2022). For example, Pradhan et al. (2021), using a panel Vector Error Correction approach on a sample of G-20 countries on the period 1961-2016, conclude that there is a positive relationship between urbanization and economic growth. A similar conclusion has been obtained by Leitão (2013) in Europe, the United States, Japan, New Zealand and Mexico from 1990 to 2008 and Ngounou et al. (2023) for African countries. Some studies show mixed results. For example, in the context of ASEAN countries and using a Granger causality test, Nguyen (2018) shows that urbanization has a positive impact on economic growth, but after a certain threshold, urbanization can impede economic growth. Analyzing the direct and indirect impact of urbanization on sustainable development, Zhang et al. (2022) conclude that these effects depend on the intensity of urban development, population density and background climate, with more pronounced positive effects in cities with cold and arid environments. On the other hand, the argument that urbanization promotes economic growth has recently been challenged by a report showing that there is no evidence that the level of urbanization affects the rate of economic growth (Pholo-Bala, 2009; Chen et al., 2014). For example, Chen et al. (2014) analyzing the correlation between urbanization and economic outcomes, conclude that there is no correlation between the speed of urbanization and the rate of economic growth worldwide. Moreover, Singh et al. (2014) show a negative impact of urbanization on economic growth in the case of the Solomon Islands. More recently, Hong et al. (2021) empirically analyze the impact of government-driven urbanization on economic growth with China’s provincial data. Their results comfort that urbanization has mitigated effects on economic growth and exhibit an “urbanization without growth” phenomenon. Also, Castells-Quintana (2017) shows that the impact of urbanization on economic growth depends of the urban environment in terms of infrastructures. A recent literature 2025 - N° 1 Revue d’Économie Régionale & Urbaine 29 Deciphering the Relationship between Structural Change and Urbanization in Africa analyzes the impact of urbanization on inequalities and shows that urbanization leads to more inequalities in the African context (Ongo Nkoa & Song, 2019) and in South Asia (Obaco et al., 2022). 2.2. Transmission channels of structural change on urbanization There is no consensus on the definition and the measure of structural change. For example, some economists equate it with industrialization (Nguimkeu and Zeufack, 2019; AfDB, 2018; Neuss, 2019; Lectard, 2017), while others measure it by diversification and/or economic complexity (Cadot et al., 2011; Hidalgo and Haussmann, 2009). We adopt the definition of the African Development Bank and consider industrialization as a proxy for structural change. Budı-Ors (2023) pointed that industrialization and urbanization are two important transformations that have shaped the past, and these transformations will continue into the future, creating political challenges as the use of land, materials and energy increasingly respects natural limits or is constrained by arguments of intergenerational equity. For some authors, structural change, captured by industrialization, leads to urbanization. For example, Chu (2020) indicated that the growth of the service production sector, high-tech industries and green industries not only promotes the process of a new type of urbanization but also accelerates the structural transformation and sustainable development of the economy. Using generalized moments and least squares methods, Peng et al (2023) find that industry plays an important direct role in urbanization processes. But in the context of developing countries, the links between urbanization and structural change appear to be very weak (Gollin et al., 2016). Urbanization is not due to the growth of manufacturing production, but to the migration of rural populations to capture mining rents. Thus, urban growth is accompanied by growth in the service sector (Gollin et al., 2016). Also focusing on developing countries, Huang et al. (2023) analyze the determinants of divergences in urbanization and industrialization paths. Their work also emphasizes the negative role of mining rents on industrialization in Africa, leading to the emergence of cities without industrialization. But Gollin et al. (2016) also explore theoretical channels through which structural change can lead to urbanization. The main channel is the reallocation of labor from agriculture to industry, which facilitates the emergence of modern cities producing tradable goods. African countries are not homogeneous regarding urbanization and structural change. For example, in Cameroon, the main industries are located in two towns, Douala and Yaoundé. This industrial concentration leads to rural exodus and the concentration of populations in these towns, which leads, according to Ongo Nkoa & Song (2019), to deepened inequalities. Two main gaps emerge from the above-mentioned empirical literature. First, despite a recent growing literature on the structural change-urbanization nexus, no study has focused on the African context. To our knowledge, only Gollin et al. (2016) 30 L. de B. E YIKE M BONGO , A. T. I ROUME A B OUEBE , L. T IAGUE Z ANFACK analyzed the effects of industrialization on urban expansion in some developing countries. Secondly, in this context, no study focuses on the impact of oil abundance in the relation between structural change and urbanization. This is a major gap given that it is well documented that oil rent has a negative impact on structural change in developing countries. -3Methods and Data To test the hypotheses formulated above, we adopt an empirical strategy based on the estimation of various econometric models using African data. In particular, we’ll be using the system Generalised Method of Moments (GMM) and instrumental variable estimators. These estimators have the advantage of solving the endogeneity problem inherent in economic studies. We then use quantile regression estimation. This section describes these empirical methods and the data used. 3.1. Data and sources The analysis of the effect of structural change on urbanization in our context is carried out for 53 African countries between 2010 and 2020. This period is justified by the availability of data on the variables in our study. The variables in this study are taken from World Bank data, in particular the World Bank’s World Development Indicator (WDI) database for 2023. The variables used in this study are grouped into two categories: the dependent variable and the independent variables. 3.1.1. The dependent variable: Urbanization To capture the urbanization rate in Africa, we use the share of urban population (% of total population). This indicator is calculated from World Bank population estimates and urban ratios from the United Nations World Urbanization Prospects. Urban percentages are the number of people living in an area defined as ’urban’ per 100 inhabitants. 3.1.2. The variable of interest: structural change Following the African Development Bank (2018) and Nguimkeu and Zeufack (2019), we capture structural change in Africa by the industrialization rate. Two main proxies are used: manufacturing value-added (% of GDP) and the share of industrial employment (% of total employment) defined as persons of working age who were engaged in the production of goods or the rendering of services for pay or profit, whether they worked during the reference period or did not work because of temporary absence from a job or working time arrangements. The industrial sector includes mining and quarrying, manufacturing, construction and utilities (electricity, gas and water), in accordance with divisions 2 to 5 (ISIC 2) or categories C to F (ISIC 3) or categories B to F (ISIC 4). 2025 - N° 1 Revue d’Économie Régionale & Urbaine 31 Deciphering the Relationship between Structural Change and Urbanization in Africa 3.1.3. Others control variables GDP per capita growth (GDPPC, annual %) is the annual percentage growth rate of GDP per capita in constant local currency. GDP per capita is gross domestic product divided by the mid-year population. GDP at purchasers’ prices is the sum of gross value added by all resident producers in the economy, plus taxes on products and minus subsidies not included in the value of products. It is calculated without deducting the depreciation of manufactured assets or the depletion and degradation of natural resources. This variable is used to capture the impact of economic growth on urbanization. Mineral rents (% of GDP): both theoretical and empirical literature suggest that abundance in mineral resources tends to promote urbanization and reduce industrialization in Africa (Gollin et al., 2016). We test this idea in this paper. The mineral rent is calculated as the difference between the production value of a stock of minerals at world prices and their total production costs. The minerals considered in the calculation are tin, gold, lead, zinc, iron, copper, nickel, silver, bauxite and phosphate. Incidence of malaria (Malaria per 1,000 population at risk): this is the number of new cases of malaria per 1,000 people at risk per year. The population at risk is defined as the population living in areas where malaria is transmitted. This variable is used as a proxy of public health infrastructures. Control of Corruption (Control_corr): Control of Corruption reflects perceptions of the extent to which public power is exercised for private gain, including both petty and grand forms of corruption, as well as the ’capture’ of the state by elites and private interests. The estimate gives the country’s score on the overall indicator, in units of a standard normal distribution, i.e. ranging from approximately -2.5 to 2.5 (Kaufmann et al., 2010). Voice and Accountability: (VoiceandAcc), captures perceptions of the extent to which a country’s citizens can participate in the selection of their government, as well as freedom of expression, freedom of association and freedom of the media. Table one shows the main descriptive statistics of all variables used in econometric analysis. 3.2. Empirical strategy To analyze the effects of structural changes on urbanization in Africa, we adopt a panel data framework and formulate the following model, consistent with the empirical framework of Brunt and García-Peñalosa (2022), Gollin et al. (2016) and Michaels et al. (2012): Urbanizationit = f (Structural changeit , Xit ) 32 (1) 2025 - N° 1 594 514 511 583 572 569 539 594 542 Urbanpop Manufacture_va Manufacture_vag Employment_I GDPPC Min_rent Malaria Control_corr VoiceandAcc Source: authors calculations. Obs Variable Table 1 – Descriptive statistics 1,025581 -0,6520288 182,3177 1,270645 0,974308 15,56865 3,289074 10,86117 44,50251 Mean 5,377856 0,6461065 150,2288 2,856333 7,115789 12,74522 10,26867 6,279062 18,29822 Std, dev, 0,1037159 -1,916457 0 0 -48,39245 2,98831 -52,80265 0,972748 10,642 Min 42,99517 1,420243 709,7933 24,82312 96,95642 31,19 84,13816 39,5935 90,092 Max WDI WDI WDI WDI WDI WDI WDI WDI WDI Sources L. de B. E YIKE M BONGO , A. T. I ROUME A B OUEBE , L. T IAGUE Z ANFACK Revue d’Économie Régionale & Urbaine 33 Deciphering the Relationship between Structural Change and Urbanization in Africa Where X is the matrix of control variables. The empirical strategy relies on the estimation of the following dynamic model using the GMM in which we investigate the correlation between urbanization and structural change, while controlling for mineral rent as a proxy of natural resources abundance. Urbanit = β0 + γUrbanit−1 + β1 Struc_changeit + β2 Min_rentit + γj Xjit + εit (2) Traditional fixed effects and random effects estimators have been shown to be inappropriate in dynamic models (Eyike-Mbongo and Djoumessi, 2024). In the case of this study, this bias is pervasive. First, there is a simultaneity bias between certain explanatory variables and the dependent variable. There is also a reverse causality between urbanization and structural change. Thus, to tackle these problems, the GMM is more appropriate (Roodman, 2009). Overall, there are two main advantages to using the GMM method. In the case of a dynamic model, this method allows us to consider temporal dynamics. The second advantage is that this estimation technique allows us to treat all exogenous variables as potentially endogenous (Roodman, 2009). Also, this method is suitable because the ratio N/T between the number of countries (N) and the length of the time span (T) is very high. But the major problem of using GMM in this study is the very short time span, that does not allow to consider many lags as instrumental variables. There are two dynamic GMM estimators: first difference GMM developed by Arellano and Bond (1991) and system GMM (Arellano and Bover, 1995; Blundell and Bond, 1998). However, the literature has identified a problem with the use of difference GMM: in some cases, series lags are not reliable instruments (Bond et al., 2003). As a result, the GMM estimator in system seems better than the one in first difference. We will therefore use this estimator in our empirical analyses. However, there is always the question of validity and multiplication of instruments. We have used the “collapse” command as recommended by Roodman (2009) in order to ensure the validity of the instruments used. We perform two complementary tests: the restriction overidentification and series correlation tests. Given the relative short time span, we just consider two lags as instruments for the dependent variable. We also use the instrumental variables estimator (IV) on panel data to estimate the equation (3) below. This estimator has a number of advantages over the GMM estimator: it is less sensitive to the problem of instrument multiplication (Baum et al., 2003). However, the question of instrument quality is omnipresent when using this estimator. We use lagged variables as instruments. To ensure instrument quality, we perform DWH and Sargan tests (Baum et al., 2003). Urbanit = β0 + β1 Struc_changeit + β2 Min_rentit + γj Xjit + εit (3) Finally, equation (3) is also estimated using quantile regression. This method provides a richer and more detailed description of the dependent variable than conventional regressions (Givard et d’Haultfoeuille, 2013). In fact, quantile regression models the relationship between a set of independent variables and specific quantiles of the dependent variable. This method has two main advantages. First, 34 L. de B. E YIKE M BONGO , A. T. I ROUME A B OUEBE , L. T IAGUE Z ANFACK it tends to resist the influence of outlying data. Secondly, it makes no assumptions about the distribution of the dependent variable (Givard et d’Haultfoeuille, 2013). There is also a reverse causality between urbanization and structural change. In fact, structural change implies industrialization and urbanization. So, a strong positive correlation between these two variables could not be considered as causality. This paper does not test the causality link between industrialization and structural change. -4Results and discussions First, we discuss the baseline results, followed by sensitivity and robustness tests. Then, in addition to the regional analysis, we analyze the impact of natural resource exploitation on the relationship between structural change and urbanization in Africa. The question of the validity of these estimates is an important one. For this reason, various instrument validation tests are proposed, in particular the AR1 and AR2 tests for system GMM estimator. 4.1. Baseline results Table 2 presents the baseline results for the effects of structural change on urbanization using a GMM approach. Column 1 presents the results of a bivariate model. The results of this estimation show that the coefficient associated with structural change is positive and statistically significant at the 1% level. This result suggests that structural change is associated with urbanization in Africa. In Columns 2 and 3, we present the results of estimations of equation (2) while introducing GDP per capita growth rate, mineral rents, control of corruption, democracy and the incidence of malaria as a proxy of public health infrastructure. Also, we find that the coefficients associated with structural transformation is positive and significant at the 1% level. This result is in line with studies showing the positive impact of industrialization on urbanization (Brunt and García-Peñalosa, 2022; Abbas et al., 2023; Cœurdacier et al., 2022). As regards the control variables, we find that all coefficients associated with GDP per capita growth rate are positive and significant, showing that economic growth is positively linked with urbanization in the African context. This result is consistent with the literature documenting a positive link between growth and urbanization (Michaels et al., 2012; Gollin et al., 2016). In addition, the results suggest that abundance of mineral resources is positively and statistically significant associated with urbanization in Africa. In fact, all the coefficients associated with mineral rent are positive and significant. This major result shows that abundance of mineral resources explains the dynamics of urbanization in Africa. The main channel that can be raised is the following: abundance in mineral resources tends to lead to corrupt political regimes. This could lead to a neglection of rural areas in terms of furniture 2025 - N° 1 Revue d’Économie Régionale & Urbaine 35 Deciphering the Relationship between Structural Change and Urbanization in Africa of primary infrastructures. This result, consistent with Gollin et al. (2016), is also consistent with the signs associated with corruption and democracy. Corruption is positively linked with urbanization while democracy is negatively linked with urbanization in the African context. 4.2. IV-Panel and quantile estimates Table 3 presents the results of the estimation of equation 3 using the panel data instrumental variable estimator. We perform the Durbin-Wu-Hausman test to check the validity of the instruments used. The results of this test show that the instruments used are not weak. The results show that structural change is also positively linked with urbanization in the African context. Also, GDP per capita growth and corruption are positively associated with urbanization. But the results suggest that the correlation between mineral rent and urbanization is not robust. Table 4 presents the results of the estimates of equation 3 using quantile regressions. We perform regressions for the quartiles Q1 corresponding to α=25%, Q2 corresponding to α=50% and Q3 corresponding to α=75%. Three main results emerge from these estimates. First, the correlation between structural change and urbanization is robust whatever the quartile level. Secondly, the relation between economic growth and urbanization depends on the level of development. The more urbanized a country is, the more growth leads to urbanization. Another important result is that mineral rents do not affect urbanization in countries with a level of urbanization close to the continental median. 4.3. Robustness checks In this section, we test the robustness of the baseline results by using an alternative proxy for structural change. We use industrial employment as a percentage of total employment. Table 5 presents the results of the estimates using the GMM estimator while table 6 shows the results of the estimates using panel instrumental variables. Consistent with the main findings from Tables 2 and 3, the analysis reveals a positive correlation between structural change, as measured by industrial employment, and urbanization in Africa. This reaffirms the initial conclusion that structural transformation, particularly through industrialization, is indeed associated with urbanization in the region. The consistency of this result across different proxies for structural change adds robustness to the findings, suggesting that the relationship between industrialization and urbanization is robust to different measurement approaches. Furthermore, the results also highlight the strong correlation between economic growth and urbanization. This relationship underscores the role of economic development as a driver of urbanization in Africa. The positive coefficients associated with economic growth indicate that regions experiencing higher rates of economic growth tend to undergo more significant urbanization processes. This finding aligns 36 L. de B. E YIKE M BONGO , A. T. I ROUME A B OUEBE , L. T IAGUE Z ANFACK Table 2 – Baseline GMM results GMMSYS GMMSYS GMMSYS VARIABLES Urbanpop Urbanpop Urbanpop Urbanpop (-1) 0.985*** 0.984*** 0.977*** (0.000639) (0.000594) (0.000794) 0.00176*** 0.000863*** 0.00286*** (2.32e-05) (3.24e-05) (0.000164) 3.24e-05** 0.000748*** (1.55e-05) (5.85e-05) 0.00137*** 0.00220*** (0.000523) (0.000778) 0.000101*** 0.000129*** (2.63e-05) (4.05e-05) Structural change GDPPCG Min_rent Incidence_malaria Control_Corruption 0.101*** (0.00792) Voice_Accountability -0.00443** (0.00182) Constant 1.192*** 1.299*** 1.707*** (0.0464) (0.0363) (0.0802) AR1 AR2 Hansen Sargan 0.0000 0.1279 0.4321 0.000 0.0010 0.2541 0.5960 0.0001 0.000 0.1873 0.2749 0.000 Observations 417 372 312 Number of code 48 43 43 Robust standard errors in parentheses *** p<0.01, ** p<0.05, * p<0.1 Source: authors. with the broader literature that emphasizes the positive link between economic growth and urbanization. On the other hand, the results demonstrate a noteworthy association between corruption and urbanization. The positive correlation suggests that regions with higher levels of corruption tend to experience more rapid urbanization. This finding is consistent with the notion that corruption may influence urbanization dynamics by skewing resource allocation and development priorities, potentially favoring urban areas over rural ones. However, it’s essential to interpret this result cautiously 2025 - N° 1 Revue d’Économie Régionale & Urbaine 37 Deciphering the Relationship between Structural Change and Urbanization in Africa Table 3 – Results using IV-panel IV-PANEL IV-PANEL IV-PANEL VARIABLES Urbanpop Urbanpop Urbanpop Structural change 0.514** 0.987*** 0.559*** (0.207) (0.217) (0.223) 1.311*** 1.386*** (0.317) (0.355) 0.298 0.496 (0.460) (0.485) 0.0527*** 0.0501*** (0.00758) (0.00824) GDPPCG Min_rent Incidence_malaria Control_Corr 3.324*** (0.224) Voice_Accountability 0.205 (0.161) Constant 4.86*** 5.15*** 5.29*** (1.655) (1.469) (1.528) Sargan DWH 0.0056 0.001 0.001 0.000 0.000 0.000 Observations 511 503 467 R-squared 0.036 0.300 0.321 Robust Standard errors in parentheses *** p<0.01, ** p<0.05, * p<0.1 Source: authors and consider the broader socio-political context in which corruption operates within African countries. 4.4. Heterogeneity analysis 4.4.1. Results by sub regions In this section, we check for the robustness of the results considering African subregional areas. Following the African Union, we divide the sample in five subregions: Northern, Southern, Central, Western and Eastern. Tables 7 and 8 provide the results of the estimates using GMM and panel-IV respectively. Also, we use the industrial employment share as a proxy of structural change. 38 L. de B. E YIKE M BONGO , A. T. I ROUME A B OUEBE , L. T IAGUE Z ANFACK Table 4 – Results using Quantile regression Q25 Q50 Q75 VARIABLES Urbanpop Urbanpop Urbanpop Structural change 0.453*** 0.250*** 0.121*** (0.060) (0.0341) (0.0922) 0.335 0.592* 0.556*** (0.297) (0.344) (0.197) 1.328*** 0.146 1.085*** (0.326) (0.257) (0.132) 0.0303*** 0.0302*** 0.0574*** (0.00855) (0.00938) (0.00548) 4.311 6.768** 1.909 (3.414) (2.952) (1.384) 0.491*** 0.137** 0.00144 (0.0874) (0.0592) (0.0622) 3.63*** 5.57*** 6.80*** (0.893) (0.726) (1.707) Pseudo R-squared 0.316 0.337 0.2912 Observations 420 420 420 GDPPCG Min_rent Incidence_malaria Control_Corr Voice_Accountability Constant Robust Standard errors in parentheses *** p<0.01, ** p<0.05, * p<0.1 The findings, as depicted in Tables 7 and 8, reveal that the relationship between structural change and urbanization remains robust across all considered subregions, except Western Africa where there is no association between these two variables. This consistency suggests that the positive association between industrialization and urbanization holds globally true within Africa. Such robustness underscores the significance of structural transformation, particularly through industrialization, as a driver of urbanization across diverse subregional contexts. Moreover, the results also indicate that the impact of economic growth and corruption on urbanization remains robust across the various subregions. The positive correlation between economic growth and urbanization suggests that regions experiencing higher rates of economic growth tend to undergo more significant urbanization processes, irrespective of their subregional categorization. Similarly, the positive association between corruption and urbanization persists across different subregions, highlighting the potentially influential role of corruption in shaping urbanization dynamics on a regional scale. 2025 - N° 1 Revue d’Économie Régionale & Urbaine 39 Deciphering the Relationship between Structural Change and Urbanization in Africa Table 5 – Robustness tests for change in measure of structural change using GMM GMMSYS GMMSYS GMMSYS VARIABLES Urbanpop Urbanpop Urbanpop Urbanpop (-1) 0.987*** 0.982*** 0.978*** (0.000440) (0.000746) (0.000682) 0.00231*** 0.0191*** 0.0125*** (0.000247) (0.000792) (0.000673) 0.000225*** 0.000605*** (2.98e-05) (6.14e-05) 0.00112 0.00138*** (0.000705) (0.000423) 6.10e-05*** -4.80e-05 (1.42e-05) (3.08e-05) Employment_industry GDPPCG Min_rent Incidence_malaria Control_Corr 0.0695*** (0.00542) Voice_Accountability -0.00388** (0.00152) Constant 1.084*** 0.998*** 1.308*** (0.0337) (0.0624) (0.0721) AR1 AR2 Hansen Sargan 0.000 0.0128 0.000 0.000 0.000 0.1712 0.001 0.025 0.000 0.2119 0.000 0.0182 Observations 477 413 345 Number of code 53 48 48 Robust Standard errors in parentheses *** p<0.01, ** p<0.05, * p<0.1 Source: authors Interestingly, the analysis reveals that democracy tends to reduce urbanization in the considered countries. This finding suggests that the relationship between democracy and urbanization may vary across different subregional contexts within Africa. While further exploration is needed to understand the underlying mechanisms driving this relationship, it underscores the importance of considering political factors alongside economic and social factors when examining urbanization dynamics. 40 L. de B. E YIKE M BONGO , A. T. I ROUME A B OUEBE , L. T IAGUE Z ANFACK Table 6 – Robustness tests for change in measure of structural change using Panel-IV (1) (2) (3) VARIABLES Urbanpop Urbanpop Urbanpop Employment_industry 0.208*** 0.519*** 0.491*** (0.0643) (0.114) (0.116) GDPPCG 0.328** 0.364** (0.157) (0.163) Min_rent 0.0924 0.0991 (0.286) (0.290) -0.0206*** -0.0193*** (0.00611) (0.00651) Incidence_malaria Control_Corr 3.172** (1.460) Voice_Accountability 0.237* (0.141) Constant 4.28*** 5.01*** 4.14*** (1.277) (1.462) (1.674) DWH Sargan 0.000 0.000 0.000 0.002 0.000 0.000 Observations 530 463 419 R-squared 0.192 0.226 0.248 Robust Standard errors in parentheses *** p<0.01, ** p<0.05, * p<0.1 Source: authors 4.4.2. Results following the oil wealth status In this section, we analyze the incidence of oil wealth on the relation between structural change and urbanization. To do so, we divide our sample according to the criterion of oil wealth. Following the World Bank, we have 16 oil-producing countries and 32 non-oil producing countries in our sample. The oil-producing countries are those countries which benefit from an oil rent. Table 9 provides the results of estimating Equation (2) using the GMM technique for each category of countries, while Table 10 presents the results using panel IV estimation to ensure the robustness of our findings. The results obtained are consistent across different estimation techniques, indicating robustness. However, a significant finding emerges from these analyses: the relationship between structural 2025 - N° 1 Revue d’Économie Régionale & Urbaine 41 42 Voice_Accountability Control_Corr Incidence_malaria Min_rent GDPPCG 0.796 (0.0928) (0.0262) 0.00654*** 0.131 (0.000467) (0.000168) 0.0593** -0.000712 (0.00824) (0.00104) -8.84e-05 -0.00809 (0.00241) (0.000591) 0.00347*** 0.00745*** (0.00960) (0.00464) 0.00552*** 0.0159* 0.0168*** (0.00585) (0.00181) Structural change 0.975*** 0.978*** Urbanpop(-1) Urbanpop Urbanpop (South) VARIABLES (North) Table 7 – Testing for regional factor using GMM 0.00119 (0.00768) -1.19e-05 (3.16e-05) 9.37e-05*** (0.000443) 0.00314*** (0.000165) 0.00141*** (0.00120) 0.000626 (0.000909) 1.002*** Urbanpop (West) -1.701 (0.137) -0.0241 (0.000686) -0.00107 (0.0215) 0.0355* (0.00218) 0.00365* (0.0185) 0.0596*** (0.00964) 0.928*** Urbanpop (Central) -0.0793 (0.0114) -0.0276** (2.21e-05) 9.19e-05*** (0.00541) -0.00137 (0.000174) 0.00792*** (0.00119) 0.00206* (0.00139) 1.013*** Urbanpop (East) Deciphering the Relationship between Structural Change and Urbanization in Africa 2025 - N° 1 4 Robust Standard errors in parentheses *** p<0.01, ** p<0.05, * p<0.1 Source: authors Number of code 31 Observations 9 64 0.021 0.419 0.000 0.000 (0.247) (0.178) 0.000 0.1732 0.000 0.000 1.460*** (1.268) 1.352*** (0.00205) AR1 AR2 Sargan Hansen Constant Table 7 – (suite) 15 9 68 0.000 0.3611 0.000 0.000 0.0015 0.0919 0.009 0.000 117 (1.420) 4.771*** (2.094) (0.0433) 0.408*** (0.000778) 11 65 0.000 0.1082 0.000 0.000 (0.0458) -0.0369 (0.0996) L. de B. E YIKE M BONGO , A. T. I ROUME A B OUEBE , L. T IAGUE Z ANFACK Revue d’Économie Régionale & Urbaine 43 44 Constant VoiceandAccountability ControlofCorruption Incidenceofmalariaper Min_rent 9.95*** (2.32) (0.267) 4.40*** -11.0** (3.007) (6.616) -1.948*** 6.269** (0.0209) (0.0662) 12.21* 0.0921*** (0.797) (0.254) 0.0289 0.433 (0.436) (0.246) -0.181 1.716*** 0.410* (0.469) (0.321) GDPPCG 1.434*** 1.075*** Structural change Urbanpop Urbanpop Southern VARIABLES Northern Table 8 – Testing for regional factor using Panel-IV 5.39*** (0.0825) 0.171** (1.605) 2.298 (0.00628) 0.0375*** (0.279) -0.000930 (0.173) 0.448*** (0.163) 0.461*** Urbanpop Western 1.23*** (0.301) 0.0211 (4.557) 29.74*** (0.0222) 0.138*** (0.720) -0.461 (0.246) 0.916*** (0.250) 2.839*** Urbanpop Central 5.28*** (0.871) 3.231*** (2.485) -4.868* (0.0109) 0.0512*** (0.489) -0.108 (0.211) 0.561*** (0.121) 0.917*** Urbanpop Eastern Deciphering the Relationship between Structural Change and Urbanization in Africa 2025 - N° 1 37 0.774 Observations R-squared Robust Standard errors in parentheses *** p<0.01, ** p<0.05, * p<0.1 Source: authors 0.000 0.002 (0.153) DWH Sargan Table 8 – (suite) 0.389 77 0.000 0.0218 (1.384) 0.454 138 0.021 0.000 (0.253) 0.736 83 0.000 0.000 (0.454) 0.376 84 0.000 0.000 (1.475) L. de B. E YIKE M BONGO , A. T. I ROUME A B OUEBE , L. T IAGUE Z ANFACK Revue d’Économie Régionale & Urbaine 45 Deciphering the Relationship between Structural Change and Urbanization in Africa Table 9 – Testing for the impact of oil using GMM Non-petroleum Petroleum VARIABLES Urbanpop Urbanpop Urbanpop(-1) 0.951*** 0.985*** (0.00638) (0.00215) Employment_industry 0.00538 0.0185*** (0.00971) (0.00367) GDPPCG 0.00147 0.000105 (0.00138) (0.000488) -0.0156 -0.00185 (0.0159) (0.00155) -0.00106*** -4.31e-05 (0.000404) (7.02e-05) 0.225*** 0.00882 (0.0821) (0.0242) -0.0141** 0.0295 (0.00691) (0.277) 3.428*** 0.862*** Min_rent Incidence_malaria Control_Corr Voice_Accountability Constant (0.414) (0.0835) AR1 AR2 Sargan Hansen 0.000 0.6511 0.000 0.000 0.000 0.4871 0.001 0.000 Observations 109 236 Number of code 16 32 Robust Standard errors in parentheses *** p<0.01, ** p<0.05, * p<0.1 Source: authors change and urbanization appears to be more pronounced and stable in oil-producing countries. This observation suggests a potentially adverse effect of oil wealth, particularly on the quality of structural change processes in Africa. The stability of the relationship between structural change and urbanization in oil-producing countries implies that despite the economic benefits associated with oil revenues, such as increased government revenue and investment opportunities, there may be underlying challenges hindering structural transformation and urban development. 46 L. de B. E YIKE M BONGO , A. T. I ROUME A B OUEBE , L. T IAGUE Z ANFACK Table 10 – Testing for the impact of oil using panel-IV Non petroleum Petroleum VARIABLES Urbanpop Urbanpo Employment_industry 0.0399 0.466*** (0.199) (0.169) 0.500*** 0.277*** (0.0290) (0.0183) 0.570 0.509** (0.978) (0.258) -0.0395** -0.0224*** (0.0183) (0.00608) 3.860 6.316*** (4.005) (1.483) -0.0717 2.939*** (0.166) (1.007) 5.52*** 4.07*** (1.801) (1.131) DWH Sargan 0.000 0.000 0.0001 0.0007 Observations 135 284 R-squared 0.390 0.460 GDPPCG Min_rent Incidence_malaria Control_Corr Voice_Accountability Constant Robust Standard errors in parentheses *** p<0.01, ** p<0.05, * p<0.1 Source: authors. One plausible explanation for this phenomenon is the phenomenon known as the "resource curse," where reliance on natural resource extraction, such as oil, can lead to a variety of negative outcomes including economic distortions, governance challenges, and limited diversification of the economy away from the resource sector. In the context of structural change and urbanization, the presence of oil wealth may divert attention and resources away from investing in sectors that drive structural transformation and urban development, leading to a less diversified and less resilient economy. This finding underscores the importance of understanding the nuanced impacts of natural resource wealth on economic development and urbanization processes. It also highlights the need for policymakers to carefully manage and diversify their economies to mitigate the potential adverse effects of reliance on natural resources. 2025 - N° 1 Revue d’Économie Régionale & Urbaine 47 Deciphering the Relationship between Structural Change and Urbanization in Africa -5Conclusion The objective of this study was to examine the effects of structural change on urbanization in Africa using panel data from 53 African countries spanning the years 2010 to 2020, sourced from the World Bank’s World Development Indicator (WDI) database. To address endogeneity and other potential biases, we employed a dynamic panel data framework. The Generalized Method of Moments (GMM) and instrumental variables (IV) estimators were utilized to account for temporal dynamics and address endogeneity concerns. Additionally, quantile regression was employed to provide a nuanced understanding of the relationship between variables across different quantiles of urbanization. Our results revealed a robust positive association between structural change and urbanization in Africa, supporting the notion that industrialization drives urbanization. Furthermore, economic growth was found to positively influence urbanization, while corruption exhibited a positive correlation with urbanization. Interestingly, democracy was negatively associated with urbanization, suggesting a nuanced relationship between political factors and urban development. The analysis also highlighted the impact of natural resource wealth, particularly oil, on the dynamics of structural change and urbanization, with oil-producing countries exhibiting a more pronounced relationship between structural change and urbanization. The findings of this study have several implications for policymakers in Africa. Firstly, fostering structural transformation, particularly through industrialization, should be a key priority for promoting urbanization and economic development. Policies aimed at promoting economic growth and reducing corruption are crucial for fostering sustainable urbanization. Moreover, careful management of natural resource wealth is essential to avoid the adverse effects of the "resource curse" on urban development. Also, it is crucial for government leaders to facilitate the entry of FDI into their countries, and to ensure there are no impediments to their operations. 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