Publications

La plupart des informations présentées ci-dessous ont été récupérées via RePEc avec l'aimable autorisation de Christian Zimmermann
Introduction : à la (re)découverte de l’école autrichienne d’économie (nationale)Gilles Campagnolo, Austriaca, Gilles Campagnolo (Eds.), Volume 89, Issue n° spécial « L’école autrichienne d’économie », Forthcoming
L’école autrichienne en Ukraine. La théorie de l’utilité marginale d’E. Slutsky (à partir d’archives inédites)Gilles Campagnolo et Valentyna Feshchenko, Austriaca, Gilles Campagnolo (Eds.), Volume 89, Issue n° spécial « L’école autrichienne d’économie », Forthcoming
Labor market shocks and youths’ time allocation in Egypt: Where does women’s empowerment come in?Marion Dovis, Patricia Augier et Clémentine Sadania, Economic Development and Cultural Change, Forthcoming
A proximal point method for difference of convex functions in multi-objective optimization with application to group dynamic problemsGlaydston de Carvalh Bento, Sandro Dimy Barbo Bitar, João Xavier da Neto, Antoine Soubeyran et João Carlos O. Souza, Computational Optimization and Applications, Forthcoming

We consider the constrained multi-objective optimization problem of finding Pareto critical points of difference of convex functions. The new approach proposed by Bento et al. (SIAM J Optim 28:1104–1120, 2018) to study the convergence of the proximal point method is applied. Our method minimizes at each iteration a convex approximation instead of the (non-convex) objective function constrained to a possibly non-convex set which assures the vector improving process. The motivation comes from the famous Group Dynamic problem in Behavioral Sciences where, at each step, a group of (possible badly informed) agents tries to increase his joint payoff, in order to be able to increase the payoff of each of them. In this way, at each step, this ascent process guarantees the stability of the group. Some encouraging preliminary numerical results are reported.

Fertile Ground for ConflictNicolas Berman, Mathieu Couttenier et Raphaël Soubeyran, Journal of the European Economic Association, Forthcoming

We investigate how variations in soil productivity affect civil conflicts. We first present a model with heterogeneous land in which variations in input prices (fertilizers) affect appropriable rents and the opportunity costs of fighting. The theory predicts that spikes in input prices increase the likelihood of conicts through their effect on income and inequality, and that this effect is magni fied when soil fertility is naturally more heterogenous. We test these predictions using data on conict events covering all Sub-Saharan African countries at a spatial resolution of 0.5 x 0.5 degree latitude and longitude over the 1997-2013 period. We combine information on soil characteristics and worldwide variations in fertilizer prices to identify local exogenous changes in input costs. As predicted, variations in soil productivity triggered by variations in fertilizer prices are positively associated with conicts, especially in cells where land endowments are more heterogeneous. In addition, we find that the distribution of land fertility both within and across ethnic groups affects violence, and that the effect of between-group heterogeneity in soil quality is magnified in densely populated areas. Overall, our findings imply that inequality in access to fertile areas { an issue largely neglected in the literature dealing with the roots of Sub-Saharan African civil wars { constitutes a serious threat to peace at the local-level.

Information Provision in Environmental Policy DesignVera Danilina et Alexander Grigoriev, Journal of environmental informatics, Forthcoming

Information provision is a relatively recent but steadily growing environmental policy tool. Its emergency and topicality are due to the current escalation of ecological threats. Meanwhile, its high complexity and flexibility require a comprehensive approach to its design, which has to be tailored for specific characteristics of production process, market structure, and regulatory goals. This work proposes such an approach and builds a framework based on a three-level mathematical program extending well-known two-level Stackelberg game by introducing one more economic agent and one extra level of this sequential game. This study provides simple and very intuitive algorithms to compute optimal multi-tier information provision policies, both mandatory and voluntary. The paper urges for the wide implementation of such efficient environmental policy design tools.

Regulation and altruismIzabela Jelovac et Samuel Kembou Nzale, Journal of Public Economic Theory, Forthcoming

We study optimal contracts in a regulator–agent setting with joint production, altruistic and selfish agents, limited liability, and uneasy outcome measurement. Such a setting represents sectors of activities such as education and healthcare 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 both the agent's effort and the joint outcome that are 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, under the conditions of our setting and when we face both moral hazard and adverse selection, the regulator maximizes welfare with a menu of contracts, which specify higher transfers for the altruistic agents and higher regulator's inputs for the selfish agents.

Immigrants' Wage Performance in a Routine Biased Technological Change Era: France 1994-2012Catherine Laffineur, Eva Moreno-Galbis, Ahmed Tritah et Jérémy Tanguy, Industrial Relations, Forthcoming
Tying the politicians’ hands: The optimal limits to representative democracyDidier Laussel et Ngo Van Long, Journal of Public Economic Theory, Forthcoming

The citizen candidate models of democracy assume that politicians have their own preferences that are not fully revealed at the time of elections. We study the optimal delegation problem which arises between the median voter (the writer of the constitution) and the (future) incumbent politician under the assumption that not only the state of the world 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 both a policy floor and a policy cap and delegating him/her the policy choice only in between the cap and the floor. The delegation interval is shown to be the smaller the greater is the uncertainty about the politician's type. These results are also applicable to settings outside the specific problem that our model addresses.

Biodiversity and its value: Conservation genetics meets economicsNoël Bonneuil et Raouf Boucekkine, Conservation Genetics Resources, Forthcoming

Does drawing economic benefit from nature impinge on conservation? This has been a subject of controversy in the literature. The article presents a management method to overcome this possible dilemma, and reconcile conservation biology with economics. It is based on recent advances in the mathematical theory of dynamic systems under viability constraints. In the case of a one-locus two-allele plant coexisting with a one-locus two-allele parasite, the method provides a rule for deciding when and to what extent the resistant or the susceptible strain should be cultivated, in the uncertain time-varying presence of the parasite. This is useful for preventing the fixation of the susceptible allele - and thereby limiting the plant's vulnerability in the medium term, should the parasite reappear.
The method thus provides an aid to decision for economic and ecology-friendly profitability.