Christophe Muller

2025-08

Perverse Impact of Agro-Pastoral Policies on the Dietary Intake of Agro-Pastoralists

Christophe Muller, Nouréini Souleymane

Abstract Agricultural policies in poor rural developing countries have the potential to improve both household nutrition and agricultural income. But can these policy consequences be reconciled? This is not obvious because many policies are deficient. Moreover, in villages, mismatches have been observed between nutrition and profit indicators. However, incomes raised by such policies may generate nutrition improvement. In Niger, a major program directed to agro-pastoralists is the 3N Initiative. Do these policies enhance households’ agricultural profit and dietary intakes? And if so, is it because of an income effect, or through alternative channels? Using an agropastoral survey conducted in 2016 Niger, we find that livestock extension services that reduce calorie intake while improving diet diversity operate mostly through an increased household’s pastoral profit. In contrast, veterinary services and low-cost livestock feed programs improve diet diversity, but do not affect profit and calories. Because livestock extension services foster households specializing in cattle and sheep rearing and sometimes switching to transhumance, they restrict their access to energy-dense cereals. This generate a perverse consequence on caloric intakes, despite rising animal calories. Therefore, nutritional policy-makers should better account for agro-pastoralist access to cereal markets and monitor whether policies generate differential incentives, especially through profit, for specific specialization or lifestyle.

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2022-04

Poverty Measurement under Income and Price Dispersions

Christophe Muller

Abstract This chapter discusses facts, methods and empirical results that pertain to poverty measurement under income and price dispersions. The correlation of prices and living standards is examined, and its origins are considered, in terms of whether such origins are related to consumer preferences, economic interactions and market imperfections. Then, the relationship of price dispersion and aggregate social indicators-including poverty measures-is analysed by combining stochastic hypotheses about prices and incomes with normative properties of social and poverty indicators. Finally, empirical results about how dispersed heterogeneous price indices affect poverty measurement, anti-poverty targeting and poverty-alleviation price reforms are reviewed.

Keywords Price Dispersion, Poverty Alleviation, Price Indices, Living Standards, Prices, Poverty

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2022-05

Residential segregation matters to racial income gaps

Florent Dubois, Christophe Muller

Abstract We contend that residential segregation should be an essential component of the analyses of socio-ethnic income gaps. Focusing on the contemporary White/African gap in South Africa, we complete Mincer wage equations with an Isolation index that reflects the level of segregation in the local area where individuals dwell. We decompose the income gap distribution into detailed composition and structure components. Segregation is found to be the main contributor of the structure effect, ahead of education and experience, and to make a sizable contribution to the composition effect. Moreover, segregation is found to be harmful at the bottom of the African income distribution, notably in relation to local informal job-search networks, while it is beneficial at the top of the White income distribution. Specific subpopulations are identified that suffer and benefit most from segregation, including for the former, little educated workers in agriculture and mining, often female, confined in their personal networks. Finally, minimum wage policies are found likely to attenuate most segregation’s noxious mechanisms, while a variety of policy lessons are drawn from the decomposition analysis by distinguishing not only compositional from structural effects, but also distinct group-specific social positions.

Keywords Residential segregation, Post-Apartheid South Africa, Distribution analysis, Generalized decompositions

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2021-13 v3

Revisiting Fertility Regulation and Family Ties in Tunisia

Olfa Frini, Christophe Muller

Abstract Background We revisit fertility regulation in Tunisia by examining the role of the extended family. As marriage is the exclusive acknowledged childbearing context, we examine fertility analysis in Tunisia through the se-quence: woman’s marriage age, post-marriage delay in the first use of contraception, and past and cur-rent contraceptive use. We trace the family socio-economic influences that operate through these deci-sions. Methods Using data from the 2001 PAP-FAM Tunisian survey, we estimate the duration and probability models of these birth control decisions. Results In Tunisia, family ties and socio-cultural environment appear to hamper fertility regulation that oper-ates through the above decisions. This is notably the case for couples whose marriages are arranged by the extended family or who benefit from financial support from both parental families. Conclusion This calls for family planning policies that address more the extended families. Keywords: Fertility regulation; Age at marriage; Birth control; Family influence; Contraception; Tunisia

Keywords Tunisia, Contraception, Family Interference, Birth control, Age at marriage, Fertility regulation

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2021-05

Terrorism, Insurgency, State Repression, and Cycles of Violence

Christophe Muller, Pierre Pecher

Abstract Over the last half century, violent conflicts between ethno-religious organizations and states have shaped the political and economic development context in developing countries. However, global empirical evidence on the dynamic and strategic underpinnings of these phenomena is lacking. Here, we investigate the dynamic violent relationships between the organizations that represent minorities at risk and the governments in Middle-Eastern and North African countries. Our estimates of dynamic panel data models of discrete strategic responses reveal dampened cycles of violence between states and insurgent politico-ethnic organizations due to violent mutual responses. However, such cycles are absent when the organizations target civilians instead, which is more likely after an insurgency spell. Finally, we provide an original game-theoretical interpretative framework for our results, which allows us to identify, on average and under sensible restrictions, the Stag Hunt game as an appropriate representation of the (possibly reduced-form) general strategic situations that link states and minority organizations in MENA.This is at odds with the frequent use of the prisoner's dilemma setting in the literature, or of other ad hoc strategic hypotheses, to analyze conflicts.

Keywords Terrorism, Insurgency, Cycles of Violence, Conflict Theory

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2021-02 v2

How does information on minimum and maximum food prices affect measured monetary poverty ? Evidence from Niger

Christophe Muller, Nouréini Sayouti

Abstract Do households facing different realizations of prices rather than a simple price alter the results of poverty analyses? To address this question, we exploit a unique dataset from Niger in which agropastoral households provide the observed minimum and maximum prices they paid for each consumed product in each season. We estimate poverty measures based on this price information using several absolute poverty line methodologies. Prices are used for valuing household consumption bundles, estimating household-specific price indices, valuing minimal calorie requirements, and extrapolating the link between food poverty and consumption. The results for Niger show statistically significant differences in the estimated chronic and dynamic poverties for these approaches, especially for international poverty comparisons and seasonal transient poverty monitoring. Specifically, using minimum and maximum prices generates gaps in the estimated poverty rates for Nigerien agropastoral households that exceed regional poverty disparities, which implies that regional targeting priorities in poverty alleviation policy would be reversed if these alternative prices are utilized. This result suggests that typically estimated poverty statistics, which assume that each household, or even cluster, faces a unique price for each product in a given period, may be less accurate for policy monitoring than generally believed.

Keywords Poverty, Prices, Niger, Social policies

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2020-29

The Contribution of Residential Segregation to Racial Income Gaps: Evidence from South Africa

Florent Dubois, Christophe Muller

Abstract In this paper, we contend that local segregation should be an essential component of the analyzes of the determination of socio-ethnic income gaps. For this, we adopt a thorough distribution decomposition approach, as a general preliminary descriptive step to prospective specific structural analyses. Focusing on the contemporary White/African gap in South Africa, we first complete Mincer wage equations with an Isolation index that reflects the level of segregation in the local area where individuals dwell. Second, we decompose the income gap distribution into detailed composition and structure components. Third, we explore the heterogeneity of segregation effects on wage gaps along three theoretical lines: racial preferences, labor market segmentation, and networks links. Segregation is found to be the main contributor of the structure effect, ahead of education and experience, and to make a sizable contribution to the composition effect. Moreover, segregation is harmful at the bottom of the African income distribution, notably in relation to local informal job-search networks, while it is beneficial at the top of the White income distribution. Only minor influences of racial preferences and labor market segmentation are found. Specific subpopulations are identified that suffer and benefit most from segregation, including for the former, little educated workers in agriculture and mining, often female, immersed in their personal networks. Finally, minimum wage policies are found likely to attenuate most segregation’s noxious mechanisms.

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2019-17

How Do Agro-Pastoral Policies Affect the Dietary Intake of Agro-Pastoralists? Evidence from Niger

Christophe Muller, Nouréini Sayouti

Abstract Agricultural policies in poor rural developing countries typically aim at improving household nutrition by raising households’ agricultural profit and presumably their dietary intake as a consequence. However, it is not clear how much of the impact of these policies goes through profit in practice. If the proportion is large, this would confirm the policy orientation and direct the attention of policy makers toward the different financial incentives. Even full activity substitution may occur, which may transform households’ lifestyles and access to nutrient sources and thereby affect their nutrition. If, in contrast, the policy impact does not go through profit, then the policy perspective should be adjusted, and a thorough examination and monitoring of its other channels of influence should be undertaken. Using statistical mediation analysis, we investigate the mechanisms underlying the effect of agricultural policies directed toward pastoralist households on their dietary intake in terms of these direct and indirect (through profit) effects. Based on an agro-pastoral survey conducted in Niger in 2016, the effects of extension services associated with better access to markets are found to be channeled mostly through pastoral profits, while this is not the case for private veterinary services and low-cost livestock feed programs. Extension services may foster specialization in cattle and sheep raising, which incentivizes households to switch toward a nomadic lifestyle and limits their access to cereals, a valuable source of calories. As a result, extension services are found to damage their calorie intake.

Keywords Agricultural household models, Niger, Mediation analysis, Agro-pastoral policies

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2019-20

Linear Quantile Regression and Endogeneity Correction

Christophe Muller

Abstract The main two methods of endogeneity correction for linear quantile regressions with their advantages and drawbacks are reviewed and compared. Then, we discuss opportunities of alleviating the constant effect restriction of the fitted-value approach by relaxing identification conditions.

Keywords Two-stage estimation, Quantile regression, Fitted-Value Approach, Endogeneity

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2019-03

Social Shock Sharing and Stochastic Dominance

Christophe Muller

Abstract Since the seminal paper of Atkinson and Bourguignon (1982), little decisive progress has been achieved in developing empirically efficient stochastic dominance criteria for multidimensional social welfare analysis. By proposing new axioms of 'Social Shock Sharing', this paper provides new intuitive justifications to imposing sign restrictions on partial derivatives of individual von Neumann-Morgenstern utility functions. These new breakthrough findings are exploited to derive necessary and sufficient stochastic dominance criteria for multidimensional social welfare comparisons, up to the sixth order, at least. Equivalent results are derived in terms of multidimensional poverty conditions. Empirically powerful discriminatory criteria are obtained by combining all social shock sharing axioms up to some high order and by deriving a dimension reduction property. An application to Egypt at the beginning of the XXIst century demonstrates the practical substantial gain in discriminating power of the approach by revealing a unambiguous continual improvement in bivariate income-education social welfare over the studied period.

Keywords Multidimensional welfare, Stochastic dominance, Temperance, Risk sharing

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2018-17

Transborder Ethnic Kin and Local Prosperity: Evidence from Night-Time Light Intensity in Africa

Christophe Muller, Pierre Pecher

Abstract Ethnicity often occupies a core role in integrated social, economic, and political development processes, which have mostly been studied within specific countries. Across countries, social and economic development may be supported by political capabilities achieved by ethnic kin abroad, although there is little hard evidence on politico-economic interactions through ethnic networks. We fill this gap by providing the first robust empirical evidence of the substantial effects of political predominance of transborder ethnic kin on local economic development in Africa. This is achieved by specifying and estimating dynamic spatial models of geolocalised luminosity and matching these data with other geolocalised information on geographic, political, and ethnic characteristics. Spatial and ethnic network effects are separately identified and jointly analysed. Not only distinct spatial effects and transborder ethnic effects are exhibited, but also are their complex dynamics and spatial distribution features in terms of local development. The results draw attention to the relevance of a broader international perspective on policies affecting ethnic politics within countries.

Keywords Local development, Ethnic networks, Institutions

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2018-08

Household Fuel Use in Rural China

Christophe Muller, Huijie Yan

Abstract The household transition from dirty to clean fuels is important because of its economic, health and environment consequences, locally, nationally and globally. In order to study fuel choices, a non-separated farm household model for fuel demands is developed. Then, discrete choice equations of fuel uses, consistent with this theoretical model, are estimated using microeconomic household panel data from rural China. The estimation results support the theoretical approach that implies that the fuel demands depend not only on income, fuel prices, and demand-side socioeconomic factors, as would occur in the standard fuel demand models in the literature, but also on food prices, agricultural assets, and original household and community characteristics that shape the household responses to market failures. Finally, we present a few policy simulations that reveal the complex substitution impact of energy price policies in China. We provide the first evidence on: price sensitivity of fuel stacking, that food prices exert some pressure on the fuel transition, the role of farm work and activity specialization in fuel choices. Policies should incorporate some of the complexity of the non-separated decisions of rural households in this context of market failures. The complex cross-price effects imply that the policy pricing mechanisms should account for all energy types and food prices. Finally, market-based policies should be coupled with policy interventions aimed at increasing the opportunity cost of dirty fuels.

Keywords China, Energy, Fuel use, Consumption demand

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2018-02

Optimal Cash Transfers with Distribution Regressions: An Application to Egypt at the Dawn of the XXIst Century

Christophe Muller

Abstract Social programmes for poverty alleviation involve eligibility rules and transfer rules that often proxy-means tests. We propose to specify the estimator in connection with the poverty alleviation problem. Three distinct stages emerge from the optimization analysis: the identification of the poor, the ranking of their priorities and the calculus of the optimal transfer amount. These stages are implemented simultaneous by using diverse distribution regression methods to generate fitted-values of living standards plugged into the poverty minimization programme to obtain the transfer amounts. We apply these methods to Egypt in 2013. Recentered Influence Function (RIF) regressions focusing on the poor correspond to the most efficient transfer scheme. Most of the efficiency gain is obtained by making transfer amounts varying across beneficiaries rather than by varying estimation methods. Using RIF regressions instead of quantile regressions delivers only marginal poverty alleviation, although it allows for substantial reduction of the exclusion of the poor.

Keywords Targeting, Optimizing estimator, Poverty

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2017-39

Fertility Regulation Behavior: Sequential Decisions in Tunisia

Olfa Frini, Christophe Muller

Abstract Fertility analysis in Tunisia is revisited by focusing on regulation instruments instead of the number of births or the number of children alive. In Muslim societies, in which marriage is the exclusive acknowledged childbearing context, a woman may be seen as starting her fertility regulation period by postponing her age at marriage. Once married, she can adjust the delay before her first birth control. Then, she can decide whether or not to use a contraceptive, and finally she can select a specific contraception method. These four decisions, approximately arranged sequentially, may somewhat interact with the sequential stages of the woman’s lifecycle and involve distinct motivations: (1) enrolment in higher education; (2) participation in the labor market; (3) a given fertility objective; and (4) dealing with middle age and old age health problems. Using data from the 2001 Tunisian PAP-FAM survey data, we estimate econometric models that provide an approximate description of fertility regulation as an outcome of the above sequential decisions. Accordingly, the significant effects of our explanatory variables gradually arise and vanish across the models as the women proceeds in her fertility regulation process. Our findings suggest that family network and sociocultural environment greatly shape the household preference for children. Although strict causality inference is beyond the possibilities of a single cross-section, the elicited correlations point to suggestive explanations that call for additional collection efforts to better capture lifecycle decisions of family members and the interactions of the extended family across this lifecycle.

Keywords Marriage duration at first birth control, Age at marriage, Fertility regulation, Contraceptive use, Contraception method, Tunisia

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2017-19

Decomposing Well-being Measures in South Africa: The Contribution of Residential Segregation to Income Distribution

Florent Dubois, Christophe Muller

Abstract Despite the influential work of Cutler and Glaeser [13], whether ghettos are good or bad is still an open and debatable question. In this paper, we provide evidence that, in South Africa, ghettos can be good or bad for income depending on the studied quantile of the income distribution. Segregation tends to be beneficial for rich Whites while it is detrimental for poor Blacks. Even when we find it to be also detrimental for Whites, it is still more detrimental for Blacks. We further show that the multitude of results fuelling this debate can come from misspecification issues and selecting the appropriate sample for the analysis. Finally, we quantify the importance of segregation in the income gap between Blacks and Whites in the post-Apartheid South Africa. We find that segregation can account for up to 40 percent of the income gap at the median. It is even often a larger contribution than education all across the income distribution.

Keywords Post-Apartheid South Africa, Generalized decompositions, Income distribution, Residential segregation

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2017-18

Segregation and the Perception of the Minority

Florent Dubois, Christophe Muller

Abstract In his seminal work, Schelling (1971) shows that even individual preferences for integration across groups may generate high levels of segregation. However, this theoretical prediction does not match the decreasing levels of segregation observed since the 1970s. We construct a general equilibrium model in which preferences depends on the number of peers and unlike individuals, but also on the benefit (or loss) they attribute to the economic and social life that a minority member brings with him, which we call their “perception of the minority”. In this framework, there always exists a structure of the preferences for which integrated equilibria emerge and are stable. Even when individuals are all prejudiced against other groups, there is still a level of the perception of the minority for which integration is a stable outcome. We then propose an econometric specification in which the structural preference parameters can be identified. In the case of South Africa, our estimates of preferences provide evidence for a dynamics toward increasing integration as the effect of the perception of the minority is found positive and significant, and overcome both racism and homophily by between roughly one and four times.

Keywords Post-Apartheid South Africa, Residential segregation, Racial preferences, Structural estimation

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2017-16

A Robust Test of Exogeneity Based on Quantile Regressions

Tae-Hwan Kim, Christophe Muller

Abstract In this paper, we propose a robust test of exogeneity. The test statistics is constructed from quantile regression estimators, which are robust to heavy tails of errors. We derive the asymptotic distribution of the test statistic under the null hypothesis of exogeneity at a given quantile. Then, the finite sample properties of the test are investigated through Monte Carlo simulations that exhibit not only good size and power properties, but also good robustness to outliers.

Keywords Régression quantile, Endogeneity, Two-stage estimation, Hausman test

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2017-15

Ethnic Horizontal Inequity in Indonesia

Christophe Muller

Abstract For the first time in Indonesia, we jointly analyse several economic statistics and ethnic diversity indicators at national and local levels. Nationally, we find very high levels of economic inequality, measured from household asset values or consumption expenditure. In contrast, the levels of ethnic diversity, while non-negligible, are much lower, whether they reflect fractionalization, polarization, or horizontal inequity based on individual living standards. All horizontal inequity indicators surged after the Asian economic crisis. Horizontal inequity based on education is much lower and decreasing. Finally, we provide tentative explanations of local horizontal inequity in regressions that show a mixed pattern of socioeconomic influences.

Keywords Community activities, Ethnic diversity, Inequality, Indonesia

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2012-22 v3

Wages and On-the-Job Training in Tunisia

Christophe Muller, Christophe J. Nordman

Abstract Training costs may hamper intra-firm human capital accumulation. As a consequence, firms may be tempted to have workers paying for their on-the-job training (OJT). In this paper, we analyse the links of OJT and worker remuneration in the suburb of Tunis, using case-study data for eight firms. We find that the duration of former OJT negatively influences starting wages, while there is no anticipated effect of future training on wages at the firm entry. In contrast, current wages are positively affected by former OJT, but negatively affected by ongoing OJT. These results provide very rare empirical support in LDCs for classical human capital theories and cost sharing theories applied to OJT.

Keywords Wage, On-the-job training, Tunisia

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2015-22 v3

Heterogeneity and Non-Constant Effect in Two-Stage Quantile Regression

Christophe Muller

Abstract Heterogeneity in how some independent variables affect a dependent variable has become a major topic of study in econometrics and statistics. In this respect, this paper addresses the question of constant versus non-constant effect through quantile regression modeling. For linear quantile regression under endogeneity, it is often believed that the fitted- value setting (i.e., replacing endogenous regressors with their exogenous fitted-values) implies constant effect (that is: the coefficients of the covariates do not depend on the considered quantile, except for the intercept). Here, it is shown that, under a weakened instrumental variable restriction, the fitted-value setting can allow for non-constant effect, even though only the constant-effect coefficients of the model can be identified. An application to food demand estimation in 2012 Egypt shows the practical potential of this approach.

Keywords Two-stage estimation, Fitted-value setting, Quantile regression, Non constant effect, Partial identification

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2016-23

On the Number of Social Reforms in MENA Economies

Christophe Muller, Klarizze Anne Martin Puzon

Abstract By constructing a novel measure on the frequency of changes in social protection policies, we provide preliminary, yet new evidence on the determinants of social security reforms in Middle East and North Africa (MENA) countries. This fills a gap in literature where analyses of MENA social policies have been lacking due to limited data. Using panel data for seventeen countries from 1961 to 2015, we estimate RE Poisson regression models. Our results indicate that growth in national income and the frequency of social reform in MENA countries are related, first positively for low growth rates, then negatively for high growth rates. This finding is completed by the negative effects of oil production and of the population size on the number of social reforms. Among the avenues of interpretation we examined - investment model, social objectives pursued by the government, and socio-political equilibrium - this is the first one which seems to be better able to fit our results, accompanied by political disturbances.

Keywords Social protection, Welfare programs, Middle-East and North-Africa

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2016-13

Household Fuel Use in Developing Countries: Review of Theory and Evidence

Christophe Muller, Huijie Yan

Abstract Because of recent concerns about the negative externalities of traditional fuel use on the environment and health, the issue of the household fuel transition in developing countries, from dirty fuels towards clean fuels, has received growing research attention. This paper provides an up-to-date survey of the economic literature on household fuel use in these countries. First, we present the conceptual and theoretical frameworks. Then, we discuss the empirical results that show how a wide range of factors drive the household fuel transition. Finally, we suggest priorities for policy initiatives and highlight areas of future research.

Keywords Household decisions, Fuel transition, Energy consumption

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2016-01

Multidimensional Poverty in Seychelles

Christophe Muller, Asha Kannan, Roland Alcindor

Abstract The typically used multidimensional poverty indicators in the literature do not appear to be relevant for middle-income countries like Seychelles and can yield unrealistic estimates of poverty. In particular, the deprivations typically considered in such measures little occurs in middle-income economies. In this paper, we propose a new approach to measuring multidimensional poverty in Seychelles based on a mix of objective and subjective information about households living conditions, and on how these households view their spending priorities. The empirical results based on our new approach show that a small but non-negligible minority of Seychellois can be considered as multidimensionally poor, mostly as not being able to satisfy their shelter and food basic needs. Finally, the Seychelles social aid programs run by the Agency for Social Protection is poorly targeted whether evaluated in terms of multidimensional poverty or in terms of one-dimensional monetary poverty.

Keywords Poverty, Multidimensional wellbeing, Destitution, Seychelles

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2014-18

A Test of Separability of Consumption and Production Decisions of Farm Households in Ethiopia

Christophe Muller

Abstract In this paper, we test and reject the separability of production and consumption decisions of agricultural households in Ethiopia, using data from a rural household survey conducted in 1994 and an estimated labour demand equation. We also elicit socio-demographic and asset variables that are positively linked with agricultural labour demands. These results reflect the limited development of fully organised labour markets in rural Ethiopia. They also imply that purely market-driven agricultural policies, e.g., price subsidies or taxes, may have only limited or perverse impacts, and should be complemented by policies directly affecting household decisions, such as food aid, technology transfer, free supply of fertilizers, etc.

Keywords Agricultural Household, Separability, Ethiopia

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2013-42

A Test for Endogeneity in Conditional Quantiles

Tae-Hwan Kim, Christophe Muller

Abstract In this paper, we develop a test to detect the presence of endogeneity in conditional quantiles. Our test is a Hausman-type test based on the distance between two estimators, of which one is consistent only under no endogeneity while the other is consistent regardless of the presence of endogeneity in conditional quantile models. We derive the asymptotic distribution of the test statistic under the null hypothesis of no endogeneity. The finite sample properties of the test are investigated through Monte Carlo simulations, and it is found that the test shows good size and power properties in finite samples. As opposed to the test based on the IVQR estimator of Chernozhukov and Hansen (2006) in the case of more than a couple of variables, our approach does not imply an infeasible computation time. Finally, we apply our approach to test for endogeneity in conditional quantile models for estimating Engel curves using UK consumption and expenditure data. The pattern of endogeneity in the Engel curve is found to vary substantially across quantiles

Keywords Régression quantile, Endogeneity, Two-stage estimation, Hausman test, Engel curve

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2013-41

Task Organization, Human Capital and Wages in Moroccan Exporting Firms

Christophe Muller, Christophe J. Nordman

Abstract We conduct a case study of the linkages of task organization, human capital accumulation and wages in Morocco, using matched worker-firm data for Electrical-mechanical and Textile-clothing industries. In order to integrate task organization into the interacting processes of workers' training and remunerations, we assume a recursive model, which is not rejected by our estimates: task organization influences on-the-job training that affects wages. Beyond sector and gender determinants, assignment of workers to tasks and on-the-job training is found to depend on former education and work experience in a broad sense. Meanwhile, participation in on-the-job training is stimulated by being assigned to a team, especially of textile sector and for well-educated workers. Finally, task organization and on-the-job training are found to affect wages.

Keywords Morocco, Wages, On-the-job training, Human capital, Task organization

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2013-06

Group Violence, Ethnic Diversity and Citizen Participation: Evidence from Indonesia

Christophe Muller, Marc Vothknecht

Abstract We study the impact of violent conflict on social capital, as measured by citizen participation in community groups, defined by four activity types: governance, social service, infrastructure development and risk-sharing. Combining household panel data from Indonesia with conflict event information, we find an overall decrease in citizen contributions in districts affected by group violence in the early post-Suharto transition period. However, participation in communities with a high degree of ethnic polarization is less affected, and is even stimulated for local governance and risk-sharing activities. Moreover, individual engagement appears to depend on the involvement of other members from the same ethnic group, which points toward building of intra-ethnic social networks in the presence of violence. Finally, our results show the danger of generalization when dealing with citizen participation in community activities. We find a large variety of responses depending on the activity and its economic and social functions. We also find large observed and unobserved individual heterogeneities of the effect of violence on participation. Once an appropriate nomenclature of activities is used and controls for heterogeneity are applied, we find that the ethnic and social configuration of society is central in understanding citizen participation.

Keywords Violent Conflict, Citizen participation, Local Public Goods

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2012-21

Bias Transmission and Variance Reduction in Two-Stage Quantile Regression

Tae-Hwan Kim, Christophe Muller

Abstract In this paper, we propose a variance reduction method for quantile regressions with endogeneity problems. First, we derive the asymptotic distribution of two-stage quantile estimators based on the fitted-value approach under very general conditions on both error terms and exogenous variables. Second, we exhibit a bias transmission property derived from the asymptotic representation of our estimator. Third, using a reformulation of the dependent variable, we improve the efficiency of the two-stage quantile estimators by exploiting a trade-off between an asymptotic bias confined to the intercept estimator and a reduction of the variance of the slope estimator. Monte Carlo simulation results show the excellent performance of our approach. In particular, by combining quantile regressions with first-stage trimmed least-squares estimators, we obtain more accurate slope estimates than 2SLS, 2SLAD and other estimators for a broad range of distributions.

Keywords Two-stage estimation, Variance reduction, Quantile regression, Asymptotic bias

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