Documents de travail

Basic sanitation facilities are still lacking in large parts of the developing world, engendering serious environmental health risks. Interventions commonly deliver in-kind or cash subsidies to promote private toilet ownership. In this paper, we assess an intervention that provides information and behavioral incentives to encourage villagers in rural Mali to build and use basic latrines. Using an experimental research design and carefully measured indicators of use, we find a sizeable impact from this intervention: latrine ownership and use almost doubled in intervention villages, and open defecation was reduced by half. Our results partially attribute these effects to increased knowledge about cheap and locally available sanitation solutions. They are also associated with shifts in the social norm governing sanitation. Taken together, our findings, unlike previous evidence from other contexts, suggest that a progressive approach that starts with ending open defecation and targets whole communities at a time can help meet the new Sustainable Development Goal of ending open defecation.

I develop a model of strategic communication to study information aggregation in an alliance between multiple players. An alliance exhibits four features: i) imperfect private information among players; ii) substitutability in actions; iii) constraints on the action set; and iv) preference heterogeneity (biases). The main result of the paper derives conditions for full information aggregation within the alliance under a public communication protocol. Full information aggregation ensues as long as players' biases are sufficiently cohesive with respect to the constraints on the action set. When players can (costlessly) choose an action set ex ante, I derive the precise conditions on the minimal action set such that there is full information aggregation. Comparative statics uncovers two sources for the differences in the size of the minimal action set between players: bias over outcomes (preference effect) and degree of interdependency (interdependency effect). The results are discussed in the context of burden sharing incentives during military interventions within NATO.

We propose a new correlation measure for functionally correlated variables based on local linear dependence. It is able to detect non-linear, non-monotonic and even implicit relationships. Applying the classical linear correlation in a local framework combined with tools from Principal Components Analysis the statistic is capable of detecting very complex dependences among the data. In a first part we prove that it meets the properties of independence, similarity invariance and dependence and the axiom of continuity. In a second part we run a numerical simulation over a variety of dependences and compare it to other dependence measures in the literature. The results indicate that we outperform existing coefficients. We also show better stability and robustness to noise.

In this paper we investigate on Multivariate GARCH models to assess the co-movements between stock prices of american firms listed on main markets and fundamentals. Co-movements can be seen as correlations. The latter are usually estimated via standard GARCH models such as the Dynamic Conditional Correlation (Engle, 2002) or the Baba-Engle-Kraft-Kroner (Baba et al., 1990). Nevertheless more flexible models such as the Orthogonal GARCH of Alexander (2001) can be used as well. We also introduce a new Semi-parametric Orthogonal GARCH as a natural non-linear extension of the Orthogonal GARCH. A Montecarlo simulation is conducted to evaluate finite sample performance of each model before applying them to the data. Empirical results show evidence that during crises, prices are less correlated with fundamentals that in normal periods.

The article conducts a comparative study between Ricœur’s and Rawls’ thought on justice. Whereas Ricoeur focuses on the dialectic between the just and the good, Rawls is concerned with the ideal conditions under which a universal consensus on the principles of justice may be reached. Ricœur gives much importance to reading Rawls. He offers many commentaries, especially on Rawls’s major contribution, A Theory of Justice. This chapter focuses on such comments and on the relating paradoxical interpretation of Rawls’s approach to justice Ricœur provides. First, this chapter suggests that, with his interpretation of Rawls’s major contribution, Ricœur contributes to put the light on the conflicts between the just and the good. These conflicts are the key elements of what may be referred to as the aporia of the just, which consists in the contradictory requirements coming from the just considered as a virtue of either institutions or individuals. Second, this chapter shows that whereas the aporia is a major problem in Rawls’ approach to justice, it is at the core of the dialectic dynamic Ricœur sees within moral life. In his work, the aporia leads to what we call the three paradoxes of justice, which are the paradoxes with legal, distributive and political justice. Considering such paradoxes, Ricœur takes the ethics of practical wisdom as a necessary recourse. The latter provides fair decision makers with the resources needed for the aporia to be, if not resolved, at least eased.

We develop a model of cross-border acquisitions in which the foreign acquirer's ownership choice reflects a trade-off between easing the target's credit constraints and the costs of operating in an environment with weak institutions. Data on domestic and foreign acquisitions in emerging markets over the period 1990-2007 support the model predictions. The share of full foreign acquisitions is higher in sectors more reliant on external finance, in countries with lower financial development, and in countries with higher institutional quality. Sectoral external finance dependence accentuates the effect of country-level financial development and institutional quality. By contrast, the level of foreign ownership in partial acquisitions is insensitive to institutional factors and depends weakly on financial factors.

This paper proposes a new model with time-varying slope coefficients. Our model, called CHAR, is a Cholesky-GARCH model, based on the Cholesky decomposition of the conditional variance matrix introduced by Pourahmadi (1999) in the context of longitudinal data. We derive stationarity and invertibility conditions and prove consistency and asymptotic normality of the Full and equation-by-equation QML estimators of this model. We then show that this class of models is useful to estimate conditional betas and compare it to the approach proposed by Engle (2016). Finally, we use real data in a portfolio and risk management exercise. We find that the CHAR model outperforms a model with constant betas as well as the dynamic conditional beta model of Engle (2016).

Logarithms of prices of financial assets are conventionally assumed to follow drift-diffusion processes. While the drift term is typically ignored in the infill asymptotic theory and applications, the presence of nonzero drifts is an undeniable fact. The finite sample theory and extensive simulations provided in this paper reveal that the drift component has a nonnegligible impact on the estimation accuracy of volatility and leads to a dramatic power loss of a class of jump identification procedures. We propose an alternative construction of volatility estimators and jump tests and observe significant improvement of both in the presence of nonnegligible drift. As an illustration, we apply the new volatility estimators and jump tests, along with their original versions, to 21 years of 5-minute log-returns of the NASDAQ stock price index.

This paper analyzes the behavior of cross-country growth rates with respect to resource abundance and dependence. We reject the linear model that is commonly-used in growth regressions in favor of a multiple-regime alternative. Using a formal sample-splitting method, we find that countries exhibit different behaviors with respect to natural resources depending on their initial level of development. In high-income countries, natural resources play only a minor role in explaining the differences in national growth rates. On the contrary, in low-income countries abundance seems to be a blessing but dependence restricts growth.

We study the gains from trade in a new model with oligopolistic competition, firm heterogeneity, and innovation. Lowering trade costs reduces markups on domestic sales but increases markups on export sales, as firms do not pass the entire reduction in trade costs onto foreign consumers. Trade liberalisation can also reduce the number of firms competing in each market, thereby increasing markups on both domestic and export sales. For the majority of exporters, however, the pro- competitive effect prevails and their average markups decline. The incomplete pass-though and the reduction in the number of competitors instead dominate for top-exporters – the top 0.1% of firms – which end up increasing their markup. In a quantitative exercise we find that the aggregate effect of trade-induced markup changes is pro-competitive and accounts for the majority of the welfare gains from trade. Trade-induced changes in competition affect survival on domestic and export markets and firms’ decision to innovate. All exporters, and especially the top exporters, increase their market size after liberalisation which, in turn, encourages them to innovate more. Hence, top exporters contribute negatively to welfare gains by increasing their markups but positively by increasing innovation and productivity. Firms’ innovation response accounts for a small but non-negligible share of the welfare gains while the contribution of selection is U-shaped, being negative for small liberalisations and positive otherwise. A more globalised economy is therefore populated by larger, fewer and more innovative firms, each feature representing an important source of the gains from trade.

We first clarify the precise theoretical foundations behind the notion of diffusion centrality. This allows us to address a minor inconsistency in the model description of Banerjee et al. (2013). We then identify unnatural implicit assumptions in the model of political intermediation proposed by Cruz, Labonne & Querubfn (2017). We introduce two extensions of diffusion centrality, targeting centrality and reachability, which we believe better capture features of contexts with targeted requests. We derive general explicit formulas to compute these new measures.

In this paper we examine the investment strategy of sovereign wealth funds (SWFs) of the Gulf Cooperation Council (GCC) countries. GCC SWFs are considered as relatively opaque investors and strongly politicized, raising some concerns for perceived political and security risks. We investigate what are the drivers of majority cross- border equity acquisitions made by these institutional investors over the period 2006-2015. Using both Logit and ordered Logit models, we test if the usual determinants of SWFs investments still stand when we look at influential (> 10%) or majority (> 50%) acquisitions made by GCC SWFs. We find that GCC SWFs do not consider financial characteristics of the targeted firms when they acquire large cross-border stakes but rather the characteristics of the country (countries in the European union and/or countries with a high level of shareholders protection), suggesting that their motives may go beyond pure profit maximization. We also find that transparent funds are more likely to take influential or majority stakes and that they do so predominantly in non-strategic sectors. Overall, our results indicate that even if GCC SWFs do not seek only for financial returns, acquiring majority stakes is not a lever for GCC governments to get strategic interests in the target countries.

Over the period 1994-2012, immigrants’ wage growth in France has outperformed that of natives on average by more than 14 percentage points. This striking wage growth performance occurs despite similar changes in employment shares along the occupational wage ladder. In this paper we investigate the sources of immigrants’ relative wage performance focusing on the role of occupational tasks. We first show that immigrants’ higher wage growth is not driven by more favorable changes in general skills (measured by age, education and residence duration), and then investigate to what extent changes in task-specific returns to skills have contributed to the differential wage dynamics through two different channels: different changes in the valuation of skills (“price effect”) and different occupational sorting (“quantity effect”). We find that the wage growth premium of immigrants is not explained by different changes in returns to skills across occupational tasks but rather by the progressive reallocation of immigrants towards tasks whose returns have increased over time. Immigrants seem to have taken advantage of ongoing labor demand restructuring driven by globalization and technological change. In addition im- migrants’ wages have been relatively more affected by minimum wage increases, due to their higher concentration in this part of the wage distribution.

We propose a model of non-balanced endogenous growth in which the final good, which can be either consumed or used as capital, is produced using two intermediate inputs, one being “knowledge-intensive”. Agents working in the knowledge-intensive sector need to accumulate technological knowledge and thus have to decide how to split their individual unit of time between accumulation of technological knowledge (research) and work. Agents working in the second sector do not need to accumulate knowledge and thus devote all their individual unit of time to work. Individual knowledge therefore becomes a labor-augmenting factor, and knowledge accumulation leads to an unbounded increase in TFP in the knowledge-intensive sector, and thus to endogenous capital deepening. The asymmetry in the growth rates of TFP leads to non-balanced growth. Labor (number of workers) reallocations across sectors occur, leading to a greater increase in output for the knowledge-intensive sector. We show that non-balanced growth is consistent with Kaldor facts, as the asymptotic equilibrium is above all characterized by a constant interest rate and capital share in national income. However, the economy follows a growth path converging to a particular level of wealth that depends on the initial price of capital and knowledge. As a consequence, countries with the same fundamentals but lower initial wealth will be characterized by lower asymptotic wealth. We therefore extend the Lucas [19] finding and prove the existence of non-convergence across countries in a framework with structural change.

In this paper we investigate if government balanced-budget rules together with endogenous taxation may lead to aggregate instability in an endogenous growth framework. After highlighting the differences with the exogenous growth framework, we prove that under counter-cyclical consumption taxes, while there exists a unique balanced growth path, sunspot equilibria based on self-fulfilling expectations occur through a form of global indeterminacy. In addition, we argue that this result is empirically plausible for a large set of OECD countries and that it may also emerge with endogenous income taxes.

We investigate the extent to which standard one sector RBC models with positive externalities and variable capacity utilization can account for the large hump- shaped response of output when the model is submitted to a pure sunspot shock. We refine the Benhabib and Wen (2004) model considering a general type of additive separable preferences and a general production function. We provide a detailed theoretical analysis of local stabilities and local bifurcations as a function of various structural parameters. We show that, when labor is infinitely elastic, local indeterminacy occurs through Flip and Hopf bifurcations for a large set of values for the elasticity of intertemporal substitution in consumption, the degree of increasing returns to scale and the elasticity of capital- labor substitution. Finally, we provide a detailed quantitative assessment of the model and conclude with mixed results. We show that although the model is able theoretically to generate a hump-shaped dynamics of output following an i.i.d. sunspot shock under realistic parameter values, the hump is too persistent for the model to be considered fully satisfactory from an empirical point of view.

This is an introduction to the special section on financial frictions and debt constraints.

We study physicians’ incentives to use personalized medicine techniques, replicating the physician’s trade-offs under the option of personalized medicine information. In a laboratory experiment where prospective physicians play a dual-agent real-effort game, we vary both the information structure (free access versus paid access to personalized medicine information) and the payment scheme (pay-for-performance (P4P), capitation (CAP) and fee-for-service (FFS)) by applying a within-subject design. Our results are threefold. i) Compared to FFS and CAP, the P4P payment scheme strongly impacts the decision to adopt personalized medicine. ii) Although expected to dominate the other schemes, P4P is not always efficient in transforming free access to personalized medicine into higher quality patient care. iii) When it has to be paid for, personalized medicine is positively associated with quality, suggesting that subjects tend to make better use of information that comes at a cost. We conclude that this last result can be considered a “commitment device”. However, quantification of our results suggests that the positive impact of the commitment device observed is not strong enough to justify generalizing paid access to personalized medicine.

In this paper, we are interested in the interplay between real estate bubble, aggregate capital accumulation and taxation in an overlapping generations economy with altruistic households. We consider a three-period overlapping generations model with three key elements: altruism, portfolio choice, and financial market imperfections. Households realise different investment decisions in terms of asset at different periods of life, face a binding borrowing constraint and leave bequests to their children. We show that altruism plays a key role on the existence of a productive real estate bubble, i.e. a bubble in real estate raising physical capital stock and aggregate output. The key mechanism relies on the fact that a real estate bubble raises income of retired households. Because of higher bequests, there children are able to invest more in productive capital. Introducing fiscal policy, we show that raising real estate taxation dampens capital accumulation.

We study the implications of structural models of non-equilibrium thinking, in which players best respond while holding heterogeneous beliefs on the cognitive levels of others. We introduce an inclusive cognitive hierarchy model, in which players are capable of projecting the self to others in regard to their cognitive level. The model is tested in a laboratory experiment of collective decision-making, which supports inclusiveness. Our theoretical results show that inclusiveness is a key factor for asymptotic properties of deviations from equilibrium behavior. Asymptotic behavior can be categorized into three distinct types: naïve, Savage rational with inconsistent beliefs, and sophisticated.

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.

This paper analyses the effect of a pay-as-you-go pension system on the evolution of capital and pollution, and on the efficiency of an environmental versus health policy. In an overlapping generations model (OLG), we introduce endogenous longevity that depends on pollution and health expenditures. Global dynamics may display multiple balanced growth paths (BGP). We show that by discouraging savings, a policy that promotes the pension system enlarges the environmental poverty trap. More surprisingly, the environmental policy has contrasted effects according to the significance of the pension system. If it has a low size, a raise of the environmental policy enlarges the environmental poverty trap and leads to a rise in capital over pollution at the highest stationary equilibrium. In contrast, in economies where intergenerational solidarity is well developed, capital over pollution decreases at the highest BGP. In such a case, the environmental policy does not necessarily lead to a better longevity and growth.

We solve a linear-quadratic model of a spatio-temporal economy using a polluting one-input technology. Space is continuous and heterogenous: locations differ in productivity, nature self-cleaning technology and environmental awareness. The unique link between locations is transboundary pollution which is modelled as a PDE diffusion equation. The spatio-temporal functional is quadratic in local consumption and linear in pollution. Using a dynamic programming method adapted to our infinite dimensional setting, we solve the associated optimal control problem in closed-form and identify the asymptotic (optimal) spatial distribution of pollution. We show that optimal emissions will decrease at given location if and only if local productivity is larger than a threshold which depends both on the local pollution absorption capacity and environmental awareness. Furthermore, we numerically explore the relationship between the spatial optimal distributions of production and (asymptotic) pollution in order to uncover possible (geographic) Environmental Kuznets Curve cases.

Although most Microfinance Institutions (MFIs) invest in non-financial services such as business training, empirical evidence on the impact of training on microborrowers’ performance is at best mixed. We address this issue by accounting for business training allocation and its possible effects on borrowers’ behavior. We first show empirically (using data from a French MFI) that the relationship between business training allocation and borrowers’ risk is complex and non- linear. By taking this into account, we establish a positive effect of business training on the survival time of loans. These results are robust to controlling for the MFI’s selection process. We moreover propose a theoretical explanation for the non-linear relationship between borrowers’ risk and training allocation based on reverse asymmetric information, showing that it can lead to increased MFI outreach.

This paper discusses the theoretical choice of exchange rate anchors in Sub-Saharan African countries that are facing external vulnerabilities. To reduce instability, policymakers choose among promoting external competitiveness using a real anchor, lowering the burden of external debt using a nominal anchor or using a policy mix of both anchors. We observe that these countries tend to adopt mixed anchor policies. We solve a state space model to explain the determinants of and the strategy behind this policy. We find that the choice of policy mix is a two-step strategy: First, authorities choose the degree of nominal exchange rate flexibility according to the velocity of money, trade openness, foreign debt, degree of exchange rate pass-through and exchange rate target zone. Second, authorities seek to stabilize the real exchange rate depending on the degree of trade integration with the rest of world and the degree of foreign exchange interventions. We conclude with regime-switching estimations to provide empirical evidence of how these economic fundamentals influence exchange rate policy in Sub-Saharan Africa.

Dans cet article, nous nous intéressons à la coévolution des inégalités sociales, des dispositifs de solidarité et du système économique à travers trois grandes phases durant lesquelles les dispositifs de solidarité ont combiné de manière différenciée deux grandes formes de solidarité, par les proximités (par en bas) vs par l’attribution de droits (par en haut). Avec la globalisation de l'économie et la crise des années 2008 et suivantes, les inégalités sociales se sont accentuées et ont revêtu un aspect spatial marqué, jusqu’à une échelle micro-locale. En nous appuyant sur une approche théorique en termes de proximité et en nous référant aux situations largement évoquées aujourd’hui dans la littérature, nous analysons l’incapacité des politiques publiques à répondre efficacement à cette accentuation par la seule prise en compte de la proximité géographique. De nouvelles solidarités « par le bas » tendent en revanche à apporter des réponses hors de la dualité Etat-marché; elles s’apparentent à de nouvelles formes de communs que nous désignons comme « communs sociaux ». Nous montrons en quoi ces communs se distinguent des modalités anciennes de solidarité communautaire. Nous soulignons enfin à quelles conditions ces communs sont susceptibles de constituer des réponses justes et durables à l’accentuation actuelle des inégalités sociales.

Under uncertainty, mean growth of, say, wealth is often defined as the growth rate of average wealth, but it can alternatively be defined as the average growth rate of wealth. We argue that stochastic stability points to the latter notion of mean growth as the theoretically relevant one. Our discussion is cast within the class of continuous-time AK-type models subject to geometric Brownian motions. First, stability concepts related to stochastic linear homogenous differential equations are introduced and applied to the canonical AK model. It is readily shown that exponential balanced-growth paths are not robust to uncertainty. In a second application, we evaluate the quantitative implications of adopting the stochastic-stability-related concept of mean growth for the comparative statics of global diversification in the seminal model due to Obstfeld (1994).

We study the optimal delegation problem which arises between the median voter (writer of the constitution) and the (future) incumbent politician when not only the state of the world and but also the politician’s type (preferred policy) are the policy-maker’s private information. We show that it is optimal to tie the hands of the politician by imposing him/her both a policy floor and a policy cap and delegating him/her the policy choice only in between. The delegation interval is shown to be the smaller the greater is the uncertainty about the politician’s type. These results apply outside the specific problem to which our model is applied here.