Documents de travail

2017-44
Why Are Inflation Forecasts Sticky? Theory and Application to France and Germany
Frédérique Bec, Raouf Boucekkine, Caroline Jardet

This paper proposes a theoretical model of forecasts formation which implies that in presence of information observation and forecasts communication costs, rational professional forecasters might find it optimal not to revise their forecasts continuously, or at any time. The threshold time- and state-dependence of the observation review and forecasts revisions implied by this model are then tested using inflation forecast updates of professional forecasters from recent Consensus Economics panel data for France and Germany. Our empirical results support the presence of both kinds of dependence, as well as their threshold-type shape. They also imply an upper bound of the optimal time between two information observations of about six months and the co-existence of both types of costs, the observation cost being about 1.5 times larger than the communication cost.

Mots clés : forecast revision, binary choice models, information and communication costs
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2017-43
Measuring Influence in Science: Standing on the Shoulders of Which Giants?
Antonin Macé

I study the measurement of the influence of scientists based on bibliographic data. I propose a new measure that accounts for indirect influence and allows to compare scientists across different fields of science. By contrast, common measures of influence that “count citations”, such as the h-index, are unable to satisfy either of these two properties. I use the axiomatic method in two opposite ways: to highlight the two limitations of citation- counting schemes and their independence, and to carefully justify the assumptions made in the construction of the proposed measure.

Mots clés : intellectual influence, networks, comparability across fields, axiomatic method
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2017-42
Optimal Voting Rules under Participation Constraints
Antonin Macé, Rafael Treibich

We study the design of voting rules for international unions when countries’ participation is voluntary. While efficiency recommends weighting countries proportionally to their stakes, we show that accounting for participation constraints entails overweighting some countries, those for which the incentive to participate is the lowest. When decisions are not enforceable, cooperation requires the satisfaction of more stringent constraints, that may be mitigated by granting a veto power to some countries. The model has important implications for the problem of apportionment, the allocation of voting weights to countries of differing populations, where it provides a rationale for setting a minimum representation for small countries.

Mots clés : international unions, constitutional design, veto, participation constraints
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2017-41
Biodiversity, Shapely Value and Phylogenetic Trees: Some Remarks
Hubert Stahn

This paper explores the main differences between the Shapley Values of a set of taxa introduced by Haake et al. [4] and Fuchs and Jin [3], the latter having been found identical to the Fair Proportion Index (Redding and Mooers [10]). In line with Shapley [13], we identify the cooperative game basis for each of these two classes of phylogenetic games and use them (i) to construct simple formulas for these two Shapley values and (ii) to compare these different approaches. Using the set of weights of a phylogenetic tree as a parameter space, we then discuss the conditions under which these two values coincide and, if they are not the same, revisit Hartman's [5] convergence result. Finally, we compare the species ranking induced by these two values. Considering the Kendal and the Spearman rank correlation coefficient, simulations show that these rankings are strongly correlated.

Mots clés : biodiversity, phylogenetic trees, Shapley value, Fair Proportion index
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2017-40
Income Distribution by Age Group and Productive Bubbles
Xavier Raurich, Thomas Seegmuller

The aim of this paper is to study the role of the distribution of income by age group on the existence of speculative bubbles. A crucial question is whether this distribution may promote a bubble associated to a larger level of capital, i.e. a productive bubble. We address these issues in a three period overlapping generations (OC) model, where productive investment done in the first period of life is a long term investment whose return occurs in the following two periods. A bubble is a short term speculative investment that facilitates intertemporal consumption smoothing. We show that the distribution of income by age group determines both the existence and the effect of bubbles on aggregate production. We also show that fiscal policy, by changing the distribution of income, may facilitate or prevent the existence of bubbles and may also modify the effect that bubbles have on aggregate production.

Mots clés : bubble, efficiency, income distribution, overlapping generations
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2017-39
Fertility Regulation Behavior: Sequential Decisions in Tunisia
Olfa Frini
Christophe Muller

We revisit fertility analysis in Tunisia by focusing on a sequence of fertility regulation instruments, analogous to Bongaarts’ factor approach, and systematically examining family interference with these decisions. In Muslim societies, in which marriage is the exclusive socially tolerated childbearing context, the postponement of a woman’s marriage may prompt her to regulate her fertility. Regarding the other examined birth control decisions (post-marriage delay in the first use of contraception, past and current contraceptive use, choice of birth control method), the husband and the wife’s families may interfere with this decision. These successive decisions may correspond to consecutive phases in a woman’s lifecycle, such as enrolment in higher education, labor market participation, attainment of some fertility objective, and middle- and old-age health problems. In all these phases, the families may play essential roles.Using data from the 2001 PAP-FAM Tunisian survey, we estimate equations that include covariates capturing the above consecutive decisions and provide a coherent picture of the fertility regulation processes in Tunisia, including rarely observed variables on family interactions. Consistent with this setting, we find that the significant effects of covariates arise and vanish across stage-specific equations as women progress in their lifecycle. Our findings show that in Tunisia, family links and sociocultural environments greatly shape fertility regulation decisions. This calls for more intensive involvement of husbands and extended families in family planning policies. This broader perspective suggests that the resurgence of traditionalist politico-religious movements, sometimes associated with youth radicalization, may affect future fertility regulation.

Mots clés: fertility regulation, age at marriage, birth control, contraception, Tunisia
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2017-38
Application of the Ecosystem Service Concept to a Local-Scale: The Cases of Coralligenous Habitats in the North-Western Mediterranean Sea
Laure Thierry de Ville d'Avray, Dominique Ami, Anne Chenuil, Romain David, Jean-Pierre Féral

In an era when we witness the erosion of biodiversity it is essential to understand the benefits provided by ecosystems and find ways to maintain them. The concept of ecosystem service has been applied in this perspective, but mainly in large-scale surveys and on terrestrial ecosystems. The primary objective of this project is to validate the inclusion of the concept of ecosystem service as a useful input to local (small-scale) community decision making in the marine environment. A second objective is to define the beneficial services provided to local areas by the coralligenous habitats. The application of the concept of ecosystem service at a local scale is more appropriate to local regulatory and management issues. This research was focused on the complex and threatened coralligenous habitats, about which the benefits and services provided are relatively little understood. To address these issues and get around the paucity of prior research, we collected the opinions of 43 experts for two marine sites (Bay of Marseille and Port-Cros National Park) on 15 services using interviews, an online questionnaire and workshops. This work validated 10 services: the most evident were "food", "diving sites", "research" and "inspiration". We also showed that even in very close-by sites, slight differences in the bundle of services may occur, and we highlighted knowledge gaps especially concerning those services (so-called regulating services) that help to regulate environmental impacts of other phenomena. This work concluded that there is a strong need to employ a referential frame to identify and then estimate services based on local criteria such as: geographical and temporal scale, size of the population of beneficiaries, value of the benefits, and state of ecosystem well-being. These results are a basis for further evaluation of these ecosystem services and can indicate their positive contribution to local decision-making concerning the regulation and management of coralligenous habitats.

Mots clés : experts knowledge, Marseille, Port-Cros, appraisals, interviews, workshops, questionnaire, coralligenous habitats, ecosystem services, local-scale, concept application
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2017-37
Regulation and Altruism
Izabela Jelovac, Samuel Kembou Nzale

We study optimal contracts in a regulator-agent setting with joint production, altruistic and selfish agents, and uneasy outcome measurement. Such a setting represents sectors of activities such as education and health care provision. The agents and the regulator jointly produce an outcome for which they all care to some extent that is varying from agent to agent. Some agents, the altruistic ones, care more than the regulator does while others, the selfish agents, care less. Moral hazard is present due to the agent’s effort that is not contractible. Adverse selection is present too since the regulator cannot a priori distinguish between altruistic and selfish agents. Contracts consist of a simple transfer from the regulator to the agents together with the regulator’s input in the joint production. We show that a screening contract is not optimal when we face both moral hazard and adverse selection.

Mots clés : altruism, Moral Hazard, adverse selection, regulator-agent joint production
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2017-36
Procedural versus Opportunity-Wise Equal Treatment of Alternatives: Neutrality Revisited
Ali Ihsan Ozkes, M. Remzi Sanver

We revisit the neutrality requirement in social choice theory. We propose a weakening of the standard neutrality condition, by allowing for different procedural treatment for different alternatives while entailing that alternatives enjoy same ex-ante possibility to be chosen. We compare these two conditions theoretically and computationally. Furthermore, we explore social choice problems in which this weakening resolves impossibilities that stem from a fundamental tension between neutrality and anonymity. Finally, we show that in certain social choice problems, this weakening provides an immediate refinement of anonymous, neutral, and Pareto optimal social choice rules towards retaining resoluteness.

Mots clés : anonymity, neutrality, Pareto optimality, social choice functions
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2017-35
The Corridor’s Width as a Monetary Policy Tool
Guillaume A. Khayat

Credit institutions borrow liquidity from the central bank’s lending facility and deposit (excess) reserves at its deposit facility. The central bank directly controls the corridor: the non-market interest rates of its lending and deposit facilities. Modifying the corridor changes the conditions on the interbank market and allows the central bank to set the short-term interest rate in the economy. This paper assesses the use of the corridor’s width as an additional tool for monetary policy. Results indicate that a symmetric widening of the corridor boosts output and welfare while addressing the central bank’s concerns over higher risk-taking in the economy.

Mots clés : Monetary policy, interbank market, heterogeneous interbank frictions, the corridor, excess reserves, financial intermediation
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2017-34
Generalized Measures of Polarization in Preferences
Burak Can, Ali Ihsan Ozkes, Ton Storcken

We provide axiomatic characterizations for measures of polarization in profiles of preferences that are represented as rankings of alternatives. Polarization is seen as the extent to which opinions are opposed. We provide characterizations for an extension of this simple intuition on the pairs of alternatives to the cases with more than two alternatives. Our primary generalization allows for different treatment among issues, i.e., pairs of alternatives. Secondly, we show that the characterization result continues to hold when preferences are allowed to attain indifferences. Finally, we show that we can also impose a domain restriction that only allows for single-peaked preferences and retain our characterization. Our results point to a fundamental feature of measures on profile of preferences that are based on pairwise comparisons of alternatives.

Mots clés : polarization, measurement, Social Choice, single-peaked preferences
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2017-33
A Cost-Benefit Approach for Prioritizing Invasive Species
Pierre Courtois, Charles Figuières, Chloe Mulier, Joakim Weill

Biological invasions entail massive biodiversity losses and tremendous economic impacts that justify significant management efforts. Because the funds available to control biological invasions are limited, there is a need to identify priority species. This paper first review current invasive species prioritization methods and explicitly highlights their pitfalls. We then construct a cost-benefit optimization framework that incorporates species utility, ecological value, distinctiveness, and species interactions. This framework offers the theoretical foundations of a simple and operational method for the management of invasive species under a limited budget constraint. It takes the form of an algorithm for the prioritization of multiple biological invasions.

Mots clés : prioritization, biological invasions, cost/benefit, optimization, diversity
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2017-32
The Impact of a Rise in the Real Estate Transfer Taxes on the French Housing Market
Guillaume Bérard, Alain Trannoy

This paper estimates the effects of an increase in the real estate transfer taxes (RETT) rate from 3.80% to 4.50%, following an optional reform implemented in March 2014 by French départements. Not all the départements implemented the RETT increase, which is the starting point for a natural experiment: using a difference-in-differences design, we estimate two main effects. (1) An anticipation effect a month before the implementation of the reform in order to avoid the RETT increase (timing response). The total tax base increased by 28% just the month before. (2) The classic depressing effect of a tax on the equilibrium quantity (extensive margin response) is estimated to be 7% on average from March 2014 to October 2015. All in all, the average net effect corresponds to a drop of the transactions of 4.6% over a period of ten months following the implementation date. Furthermore, we estimate that the elasticity of the tax revenue to the tax increase is about 0.65, meaning that départements’ tax revenues are still on the increasing side of the Laffer curve.

Mots clés : local government, real estate market, transfer taxes, Natural experiment, anticipation
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2017-31
Optimal Population Growth as an Endogenous Discounting Problem: The Ramsey Case
Raouf Boucekkine, Blanca Martínez, José Ramón Ruiz-Tamarit

This paper revisits the optimal population size problem in a continuous time Ramsey setting with costly child rearing and both intergenerational and intertemporal altruism. The social welfare functions considered range from the Millian to the Benthamite. When population growth is endogenized, the associated optimal control problem involves an endogenous effective discount rate depending on past and current population growth rates, which makes preferences intertemporally dependent. We tackle this problem by using an appropriate maximum principle. Then we study the stationary solutions (balanced growth paths) and show the existence of two admissible solutions except in the Millian case. We prove that only one is optimal. Comparative statics and transitional dynamics are numerically derived in the general case.

Mots clés : Optimal population size, population ethics, optimal growth, endogenous discounting, optimal demographic transitions
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2017-30
A Note on Risk Sharing versus Instability in International Financial Integration: When Obstfeld Meets Stiglitz
Raouf Boucekkine, Benteng Zou

International risk sharing is one of the main arguments in favor of financial liberalization. The pure risk sharing mechanism highlighted by Obstfeld (1994) implies that liberalization is growth enhancing for all countries as it allows the world portfolio to shift from safe low-yield capital to riskier high yield capital. This result is obtained under the assumption that the volatility figures for risky assets prevailing under autarky are not altered after liberalization. This note relaxes this assumption within the standard two-country model with intertemporal portfolio choices, formally incorporating the instability effect invoked by Stiglitz (2000). We show that putting together the pure risk sharing and instability effects in the latter set-up enriches the analysis and delivers predictions more consistent with the contrasted related empirical literature.

Mots clés : optimal growth, financial liberalization, risk sharing, volatility
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2017-29
Choice with Time
João V. Ferreira, Nicolas Gravel

We propose a framework for the analysis of choice behavior when the later explicitly depends upon time. We relate this framework to the traditional setting from which time is absent. We illustrate the usefulness of the introduction of time by proposing three possible models of choice behavior in such a framework: (i) changing preferences, (ii) preference formation by trial and error, and (iii) choice with endogenous status-quo bias. We provide a full characterization of each of these three choice models by means of revealed preference-like axioms that could not be formulated in a timeless setting.

Mots clés : choice behavior, time, revealed preferences, changing preferences, learning by trial-and-error, inertia bias
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2017-28
Promotion through Connections: Favors or Information?
Yann Bramoullé, Kenan Huremovic

Connections appear to be helpful in many contexts such as obtaining a job, a promotion, a grant, a loan or publishing a paper. This may be due to favoritism or to information conveyed by connections. Attempts at identifying both effects have relied on measures of true quality, generally built from data collected long after promotion. This empirical strategy faces important limitations. Building on earlier work on discrimination, we propose a new method to identify favors and information from classical data collected at time of promotion. Under natural assumptions, we show that promotion decisions look more random for connected candidates, due to the information channel. We obtain new identification results and show how probit models with heteroscedasticity can be used to estimate the strength of the two effects. We apply our method to the data on academic promotions in Spain studied in Zinovyeva & Bagues (2015). We find evidence of both favors and information effects at work. Empirical results are consistent with evidence obtained from quality measures collected five years after promotion.

Mots clés : promotion, connections, social networks, favoritism, Information
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2017-27
Generalized Glass Ceilings in the United States – A Stochastic Metafrontier Approach
Khalid Maman Waziri

This paper highlights the limitations inherent to the stochastic earnings frontier methodology to analyzing wage discrimination and introduces the use of the metafrontier approach as an important improvement. Using US data from the Current Population Survey, we find that white women’s and black men’s maximum attainable hourly earnings represent respectively 80% and 76% of those of white men on average. Furthermore, the metafrontier approach shows that male-female and white-black differences in maximum attainable earnings are observed at all levels of human capital. This innovative methodology permits the identification of a “generalized” glass ceilings against females and blacks in the US.

Mots clés : wage differentials, discrimination, glass ceiling, stochastic frontier, stochastic metafrontier approach, sample selection correction
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2017-26
Growth and Bubbles: The Interplay between Productive Investment and the Cost of Rearing Children
Xavier Raurich, Thomas Seegmuller

As it is documented, investment of households in human capital is negatively related to the number of children individuals will have and requires some loans to be financed. We show that this negative relationship contributes to explain episodes of bubbles that are associated to higher growth rates. This conclusion is obtained in an overlapping generations model where agents choose to invest in a productive asset, that can be interpreted as human capital, and decide their number of children. A bubble allows to smooth consumption and expenses over the life-cycle, and can therefore be used to finance either productive investment or the cost of rearing children. The time cost of rearing children plays a key role in the analysis. If the time cost per child is sufficiently large, households have only a small number of children. The bubble then has a crowding-in effect because it is used to finance productive investment. On the contrary, if the time cost per child is low enough, households have a large number of children. Then, the bubble is mainly used to finance the total cost of rearing children and has a crowding-out effect on investment. Therefore, the new mechanism we highlight shows that a bubble enhances growth only if the economy is characterized by a high rearing time cost per child.

Mots clés : bubble, sustained growth, fertility
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2017-25
Trade Integration and the Polarisation of Eco-Labelling Strategies
Vera Danilina

Growing ecological concerns give rise to salient discussions of green policy impact within different social sciences domains. This research studies the outcomes of voluntary environmental labelling in autarky and upon trade integration in the presence of two types of heterogeneity, across countries and across producers. It investigates the impact of the two main types of eco-labels - multiple-criteria-based programmes (ISO Type I) and self-declared environmental claims (ISO Type II), both of which are simultaneously introduced due to the environmental concerns of consumers. The model illustrates the polarisation of eco-labels when the least productive firms tend to avoid green strategies, lower-middle productive and the most efficient firms are incentivized to greenwash, and the upper-middle productive firms choose trustful programmes. It also shows that voluntary green restrictions lead to substantial productivity effects in the market upon opening to international trade, conditionally, depending on the type of the labelling and the relative degree of environmental awareness across trading countries. The model predicts average market productivity losses and within segments productivity gains for the relatively more eco-concerned country, while the effects for the relatively less eco-concerned country are the opposite.

Mots clés : eco-labelling, Firm heterogeneity, trade integration, voluntary environmental regulation, firms productivity
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2017-24
Arranged Marriages under Transferable Utilities
Pauline Morault

In many societies, marriage is a decision taken at the familial level. Arranged marriages are documented from Renaissance Europe to contemporary rural Kenya, and are still prevalent in many parts of the developing world. However, this family dimension has essentially been neglected by the existing matching literature on marriages. The objective of this paper is to introduce family considerations into the assignment game. We explore how shifting decision-making to the family level affects matching on the marriage market. We introduce a new concept of familial stability and find that it is weaker than individual stability. The introduction of families into the marriage market generates coordination problems, so the central result of the transferable utility framework no longer holds: a matching can be family-stable even if it does not maximize the sum of total marital surpluses. Interestingly, even when the stable matching is efficient, family decision-making drastically modifies how the surplus is shared-out. These results may have fundamental implications for pre-marital investments. We find that stable matchings depend on the type of family partitioning. Notably, when each family contains one son and one daughter, familial and individual stability are equivalent.

Mots clés : marriage, family, matching, transferable utility
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2017-23
Optimal Taxation to Correct Job Mismatching
Guillaume Wilemme

This paper presents a new efficiency argument for an accommodating taxation policy on high incomes. Job seekers, applying to different segments of a frictional labor market, do not internalize the consequences of mismatch on the entry decision of firms. Workers are not selective enough, resulting in a lower average job productivity and suboptimal job creation. The output-maximizing policy is anti-redistributive to improve the quality of the jobs prospected. As an income tax affects the sharing of the match surplus, a tax on production (or profits) is required to redress the slope of the wage curve. Neither a minimum wage nor unemployment benefits can fully decentralize optimal search behaviors.

Mots clés : anti-redistributive taxation, composition externality, job quality, mismatch, search strategy
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2017-22
Working and Women’s Empowerment in the Egyptian Household: The Type of Work and Location Matter
Clémentine Sadania

This paper explores the impact of women’s work on empowerment in Egypt. Existing evidence suffers from several limitations, which I attempt to address. First, I develop an instrumental variable strategy to account for the endogeneity of work. Second, I allow for a heterogeneous impact of work, distinguishing between working in the public sector, outside work in the private sector and home-based work. Third, women’s empowerment is directly measured as their participation in household decisions. Outside work has the greatest impact. Interestingly, home-based work enhances joint decision-making. Distinguishing between urban and rural residence reveals distinct patterns of impact on decision-making.

Mots clés : women’s empowerment, employment, household decision-making
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2017-21
The Role of Inbound Tourist Flows in Promoting Exports
Zouheir El-Sahli

While it is established that tourism benefits growth through increased employment and investments, it is not well understood whether tourism has an effect on exports. This paper explores exports as an additional channel through which tourism affects domestic economic activity. Using bilateral tourist and trade flows, I explore the causal effect of tourist flows on exports. To deal with endogeneity, I construct two instruments that I use on two different sets of exporters. The evidence points in the same direction. I find that tourism affects mainly the exports of differentiated products. Specifically, I find that tourism benefits the exports from non-OECD exporters of processed food products and this effect is only estimated for South-North trade with an elasticity close to 1. For European countries, the findings point in the same direction; tourism affects differentiated consumer products and processed food with elasticity close to 1, which adds plausibility to the earlier results. I also find a lagged effect for tourism mainly on the export of consumer goods (for the two samples) and processed food products (for European countries). The results suggest that exports is an additional channel through which tourism can stimulate domestic economic activity in the tourist destination.

Mots clés : tourism, globalization, trade, gravity, terrorism
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2017-20
The Sources of Segregation
Florent Dubois

Few studies tried to quantify the relative importance of each determinants of residential segregation. This mainly comes from a reverse causality problem which hampers the identification of the quantity of interest. In this paper, we decompose the whole change in segregation between 2001 and 2011 in South Africa by using segregation curves. We show that, even without an experimental setting (which might be impossible to obtain), identification of the causal effects can still be achieved by using the dynamics of the phenomenon. The provision of basic public services appears to be one of the main explanation of the gap observed, while differences in sociodemographic characteristics play a minor role only for the least segregated neighborhoods. Housing market is responsible for an important part only among neighborhoods intermediately integrated, while past segregation and income influence moderately segregation throughout more than half of the South African neighborhoods.

Mots clés : post-apartheid South Africa, generalized decompositions, residential segregation, causal inference
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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

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.

Mots clés : 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

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.

Mots clés : post-apartheid South Africa, residential segregation, racial preferences, structural estimation
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2017-17
Do Misperceptions about Demand Matter? Theory and Evidence
Kenza Benhima, Céline Poilly

We assess theoretically and empirically the consequences of demand misperceptions. In a New Keynesian model with dispersed information, agents receive noisy signals about both supply and demand. Firms and consumers have an asymmetric access to information, so aggregate misperceptions of demand by the supply side can drive economic fluctuations. The model’s predictions are used to identify empirically fundamental and noise shocks on supply and demand. We exploit survey nowcast errors on both GDP growth and inflation, fundamental and noise shocks affecting the errors with opposite signs. We show that demand-related noise shocks have a negative effect on output and contribute substantially to business cycles. Additionally, monetary policy plays a key role in the transmission of demand noise.

Mots clés : Business cycles, information frictions, noise shocks, SVARs with sign restrictions
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2017-16
A Robust Test of Exogeneity Based on Quantile Regressions
Tae-Hwan Kim, Christophe Muller

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.

Mots clés : regression quantile, endogeneity, Two-Stage Estimation, Hausman test
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2017-15
Ethnic Horizontal Inequity in Indonesia
Christophe Muller

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.

Mots clés : community activities, ethnic diversity, Inequality, Indonesia
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2017-14
Sun, Regulation and Local Social Networks
Antoine Bonleu

The aim of this paper is to explain over-regulation and local social capital as barriers to immigration. The interest of social networks is that conflict resolution is independent of the law. Hence, if local individuals develop local social capital and regulation, foreigners without social networks are disadvantaged and can less easily migrate. We develop a two-country search-theoretic model where we endogenize the choice of procedural formalism (PF) and the network size. This model features two different equilibria: a Mediterranean equilibrium with PF and dense local social network and a Scandinavian and Anglo-Saxon equilibrium without PF and local social networks.

Mots clés : housing market regulation, local social capital, mobility, climate amenities, social networks
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2017-13
Price Discrimination and Dispersion under Asymmetric Profiling of Consumers
Paul Belleflamme, Wing Man Wynne Lam, Wouter Vergote

Two duopolists compete in price on the market for a homogeneous product. They can use a 'profiling technology' that allows them to identify the willingness-to-pay of their consumers with some probability. If both firms have profiling technologies of the exact same precision, or if one firm cannot use any profiling technology, then the Bertrand paradox continues to prevail. Yet, if firms have technologies of different precisions, then the price equilibrium exhibits both price discrimination and price dispersion, with positive expected profits. Increasing the precision of both firms’ technologies does not necessarily harm consumers.

Mots clés : price discrimination, price dispersion, Bertrand competition
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2017-12
Voluntary Management of Fisheries under an Uncertain Background Legislative Threat
Anne-Sarah Chiambretto, Hubert Stahn

We investigate the possibility for governance authorities to avoid a large part of regulatory costs, by simply backing up social norms with a threat of collective punishment. Specifically, we consider the case of fisheries in which the regulatory cap is to sustain an optimal conservation level. We identify a mandatory regulation such that, when it is used as a threat, it ensures that the cap is voluntarily implemented. The mandatory scheme is based on a incentive mechanism which secures the returns of the harvester, and a tax on potential capacity. From the status of mere threat, this mandatory regulation takes time to be enforced though. We show that such a tax scheme, even if it is applied randomly after the first occurrence of a deviation from the optimal conservation level, ensures voluntary compliance, provided a suitable choice of the capacity tax. We study the properties of this tax scheme and build an example using data on the scallop fishery in the Saint-Brieuc Bay (France) to illustrate our point.

Mots clés : voluntary agreements, fisheries, conservation policies
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2017-11
The Love for Children Hypothesis and the Multiplicity of Fertility Rates
Paolo Melindi Ghidi, Thomas Seegmuller

As illustrated by some French departments, how can we explain the existence of equilibria with different fertility and growth rates in economies with the same fundamentals, preferences, technologies and initial conditions? To answer this question we develop an endogenous growth model with altruism and love for children. We show that independently from the type of altruism, a multiplicity of equilibria might emerge if the degree of love for children is high enough. We refer to this condition as the love for children hypothesis. Then, the fertility rate is determined by expectations on the future growth rate and the dynamics are not path-dependent. Our model is able to reproduce different fertility behaviours in a context of completed demographic transition independently from fundamentals, preferences, technologies and initial conditions.

Mots clés : fertility, love for children, expectations, endogenous growth, balanced growth path
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2017-10
Bayesian Inference for TIP curves: An Application to Child Poverty in Germany
Edwin Fourrier-Nicolai, Michel Lubrano

TIP curves are cumulative poverty gap curves used for representing the three different aspects of poverty: incidence, intensity and inequality. The paper provides Bayesian inference for TIP curves, linking their expression to a parametric representation of the income distribution using a mixture of lognormal densities. We treat specifically the question of zero-inflated income data and survey weights, which are two important issues in survey analysis. The advantage of the Bayesian approach is that it takes into account all the information contained in the sample and that it provides small sample confidence intervals and tests for TIP dominance. We apply our methodology to evaluate the evolution of child poverty in Germany after 2002, providing thus an update the portrait of child poverty in Germany given in Corak et al. 2008.

Mots clés : Bayesian inference, mixture model, survey weights, zero-inflated model, poverty, Inequality
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2017-09
The Value of Biodiversity as an Insurance Device
Emmanuelle Augeraud-Véron, Giorgio Fabbri, Katheline Schubert

This paper presents a benchmark endogenous growth model including biodiversity preservation dynamics. Producing food requires land, and increasing the share of total land devoted to farming mechanically reduces the share of land devoted to biodiversity conservation. However, the safeguarding of a greater number of species is associated to better ecosystem services – pollination, flood control, pest control, etc., which in turn ensure a lower volatility of agricultural productivity. The optimal conversion/preservation rule is explicitly characterized, as well as the value of biological diversity, in terms of the welfare gain of biodiversity conservation. The Epstein-Zin-Weil specification of the utility function allows us to disentangle the effects of risk aversion and aversion to fluctuations. A two-player game extension of the model highlights the effect of volatility externalities and the Paretian sub-optimality of the decentralized choice.

Mots clés : biodiversity, stochastic endogenous growth, insurance value, recursive preferences
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2017-08
Condorcet Jury Theorem and Cognitive Hierarchies: Theory and Experiments
Yukio Koriyama, Ali Ihsan Ozkes

An information aggregation problem of the Condorcet Jury Theorem is considered with cognitive hierarchy models in which players would best respond holding heterogeneous beliefs on cognitive level of the other players. Whether the players are aware of the presence of opponents at their own cognitive level turns out to be a key factor for asymptotic properties of the deviation from the Nash behavior, and thence for asymptotic efficiency of the group decision. Our laboratory experiments provide evidence for the self-awareness condition. We obtain an analytical result showing that the difference from the standard cognitive hierarchy models arises when the best-reply functions are asymptotically expanding.

Mots clés : collective decision-making, bounded rationality, cognitive hierarchy, Condorcet Jury Theorem
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2017-07
Directed Search with Phantom Vacancies
James Albrecht, Bruno Decreuse, Susan Vroman

When vacancies are filled, the ads that were posted are generally not withdrawn, creating phantom vacancies. The existence of phantoms implies that older job listings are less likely to represent true vacancies than are younger ones. We assume that job seekers direct their search based on the listing age for otherwise identical listings and so equalize the probability of matching across listing age. Forming a match with a vacancy of age a creates a phantom of age a and thus creates a negative informational externality that affects all vacancies of age a or older. The magnitude of this externality decreases with a. The directed search behavior of job seekers leads them to over-apply to younger listings. We calibrate the model using US labor market data. The contribution of phantoms to overall frictions is large, but, conditional on the existence of phantoms, the social planner cannot improve much on the directed search allocation.

Mots clés : directed search, information persistence, vacancy age
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2017-06
Informal Risk-Sharing Cooperatives: The Effect of Learning and Other-Regarding Preferences
Victorien Barbet, Renaud Bourlès, Juliette Rouchier

We study the dynamics of risk-sharing cooperatives among heterogeneous agents. Based of their knowledge on their risk exposure and the performance of the cooperatives, agents choose whether or not to remain in the risk-sharing agreement. We highlight the key role of other-regarding preferences, both altruism and inequality aversion, in stabilizing less segregated (and smaller) cooperatives. Limited knowledge and learning of own risk exposure also contributes to reducing segregation. Our finding shed light on the mechanisms behind risk-sharing agreements between agents heterogeneous in their risk exposure.

Mots clés : Agent-based, cooperative, risk-sharing, Learning, altruism, other-regarding preferences
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2017-05
What Motivates French Pork: Political Career Concerns or Private Connections?
Brice Fabre, Marc Sangnier

This paper uses the detailed curricula of French ministers and the detailed accounts of French municipalities to identify governmental investment grants targeted to specific jurisdictions. We distinguish between municipalities in which a politician held office before being appointed as a government’s member and those in which current ministers lived during their childhood. We provide evidence that municipalities in which a minister held office during her career experience a 45% increase in the amount of discretionary investment subsidies they receive during the time the politician they are linked to serves as minister. In contrast, we do not find any evidence that subsidies flow to municipalities from which ministers originate. Additional evidence advocate in favour of a key role of network and knowledge accumulated through connections, illustrated by a persistence of the impact of intergovernmental ties.

Mots clés : pork-barrel economics, distributive politics, political connections, private connections
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2017-04
HJB Equations in Infinite Dimension and Optimal Control of Stochastic Evolution Equations via Generalized Fukushima Decomposition
Giorgio Fabbri, Francesco Russo

A stochastic optimal control problem driven by an abstract evolution equation in a separable Hilbert space is considered. Thanks to the identification of the mild solution of the state equation as v-weak Dirichlet process, the value processes is proved to be a real weak Dirichlet process. The uniqueness of the corresponding decomposition is used to prove a verification theorem. Through that technique several of the required assumptions are milder than those employed in previous contributions about non-regular solutions of Hamilton-Jacobi-Bellman equations.

Mots clés : weak Dirichlet processes in infinite dimensions, stochastic evolution equations, generalized Fukushima decomposition, stochastic optimal control in Hilbert spaces
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2017-03
Hammond’s Equity Principle and the Measurement of Ordinal Inequalities
Nicolas Gravel, Brice Magdalou, Patrick Moyes

What would be the analogue of the Lorenz quasi-ordering when the variable of interest is of a purely ordinal nature? We argue that it is possible to derive such a criterion by substituting for the Pigou-Dalton transfer used in the standard inequality literature what we refer to as a Hammond progressive transfer. According to this criterion, one distribution of utilities is considered to be less unequal than another if it is judged better by both the lexicographic extensions of the maximin and the minimax, henceforth referred to as the leximin and the antileximax, respectively. If one imposes in addition that an increase in someone’s utility makes the society better off, then one is left with the leximin, while the requirement that society welfare increases as the result of a decrease of one person’s utility gives the antileximax criterion. Incidently, the paper provides an alternative and simple characterisation of the leximin principle widely used in the social choice and welfare literature.

Mots clés : ordinal inequality, Hammond equity axiom, leximin, antileximax
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2017-02
Equality among Unequals
Mathieu Faure, Nicolas Gravel

This paper establishes an equivalence between three incomplete rankings of distributions of income among agents that are vertically differentiated with respect to some other non-income characteristic (health, household size, etc.). The first ranking is that associated with the possibility of going from one distribution to the other by a finite sequence of income transfers from richer and more highly ranked agents to poorer and less highly ranked ones. The second ranking is the unanimity of all comparisons of two distributions made by a utilitarian planer who assumes that agents convert income into utility by the same function exhibiting a marginal utility of income that is decreasing with respect to both income and the source of vertical differentiation. The third ranking is the Bourguignon (1989) ordered poverty gap dominance criterion.

Mots clés : equalization, transfers, heterogenous agents, poverty gap, Dominance, utilitarianism
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2017-01
Entrepreneurial Motivation and Business Performance: Evidence from a French Microfinance Institution
Renaud Bourlès, Anastasia Cozarenco

This article examines the link between entrepreneurial motivation and business performance in the French microfinance context. Using hand-collected data on business microcredits from a Microfinance Institution (MFI), we provide an indirect measure of entrepreneurial success through loan repayment performance. Controlling for the endogeneity of entrepreneurial motivation in a bivariate probit model, we find that "necessity entrepreneurs" are more likely to have difficulty repaying their microcredits than "opportunity entrepreneurs". However, type of motivation does not appear to make a difference to business survival. We build a stylized model to develop formal arguments supporting this outcome. We test for the robustness of our results using parametric duration models, and show that necessity entrepreneurs experience difficulties in loan repayment earlier than their opportunity counterparts, corroborating our initial findings.

Mots clés : opportunity and necessity entrepreneurs, business microcredit, loan repayment, business survival
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