Publications

Most of the information presented on this page have been retrieved from RePEc with the kind authorization of Christian Zimmermann
Equilibrium set-valued variational principles and the lower boundedness condition with application to psychologyJournal articleJing-Hui Qiu, Antoine Soubeyran and Fei He, Optimization, pp. 1-33, Forthcoming

We first give a pre-order principle whose form is very general. Combining the pre-order principle and generalized Gerstewitz functions, we establish a general equilibrium version of set-valued Ekeland variational principle (denoted by EVP), where the objective function is a set-valued bimap defined on the product of quasi-metric spaces and taking values in a quasi-ordered linear space, and the perturbation consists of a subset of the ordering cone multiplied by the quasi-metric. From this, we obtain a number of new results which essentially improve the related results. Particularly, the earlier lower boundedness condition has been weakened. Finally, we apply the new EVPs to Psychology.

Filling the “Decency Gap”? Donors’ Reaction to US Policy on International Family Planning AidJournal articleNathalie Ferrière, The World Bank Economic Review, Volume 38, Issue 1, pp. 185-207, Forthcoming

The impact of US allocation of family planning aid on other donors is studied in order to gain new insights into donor interactions. Within this context, the dominant player in the sector is the United States, whose policies on family planning undergo changes influenced by domestic debates surrounding abortion. By utilizing the Mexico City Policy and considering exposure to this particular policy as an instrumental factor, it has been observed that other donors do not immediately react to policy changes made by the United States, either contemporaneously or within one year. However, a noticeable shift occurs after a two-year period, indicating that these donors eventually align their allocation strategies with those of the United States. Further analysis of this phenomenon reveals varying patterns among different types of donors. While smaller donors exhibit a clear intention to compensate for US policy changes, larger donors display a mix of competitive tendencies and herding behavior, thereby reinforcing the impact of the Mexico City Policy after the two-year time frame.

Coercivity and generalized proximal algorithms: application-traveling around the worldJournal articleE. A. Papa Quiroz, A. Soubeyran and P. R. Oliveira, ANNALS OF OPERATIONS RESEARCH, Volume 321, Issue 1-2, pp. 451-467, Forthcoming

We present an inexact proximal point algorithm using quasi distances to solve a minimization problem in the Euclidean space. This algorithm is motivated by the proximal methods introduced by Attouch et al., section 4, (Math Program Ser A, 137: 91-129, 2013) and Solodov and Svaiter (Set Valued Anal 7:323-345, 1999). In contrast, in this paper we consider quasi distances, arbitrary (non necessary smooth) objective functions, scalar errors in each objective regularized approximation and vectorial errors on the residual of the regularized critical point, that is, we have an error on the optimality condition of the proximal subproblem at the new point. We obtain, under a coercivity assumption of the objective function, that all accumulation points of the sequence generated by the algorithm are critical points (minimizer points in the convex case) of the minimization problem. As an application we consider a human location problem: How to travel around the world and prepare the trip of a lifetime.

Sovereign wealth fund governance: A trade-off between internal and external legitimacyJournal articleJeanne Amar and Christelle Lecourt, International Business Review, Volume 32, Issue 6, pp. 102193, Forthcoming

In this paper, we provide a better understanding of what drives sovereign wealth funds (SWFs) to improve their governance. Using the most recent SWF governance scoreboard from Maire et al. (2021), we estimate a fractional response model to determine whether SWF governance disclosure norms are driven by the search for internal or external legitimacy. Overall, we find that SWFs have better governance when they originate from democratic countries with high-quality, national governance. Our results also show that SWFs tend to have better governance quality when they need to acquire external legitimacy vis-à-vis the target company and its government. In particular, we find that SWFs have an incentive to improve their governance when they are sufficiently internationalized, when the amount of foreign assets invested abroad is sufficiently large or when the amount of shares acquired in developed countries is significant. These findings demonstrate how SWFs may proactively build legitimacy in host countries when they need to adapt their foreign entry strategies. Our results have important implications for understanding the determinants of SWF governance in general.

Environment, public debt, and epidemicsJournal articleMarion Davin, Mouez Fodha and Thomas Seegmuller, Journal of Public Economic Theory, Volume 25, Issue 6, pp. 1270-1303, Forthcoming

We study whether fiscal policies, especially public debt, can help to curb the macroeconomic and health consequences of epidemics. Our approach is based on three main features: we introduce the dynamics of epidemics in an overlapping generations model to take into account that old people are more vulnerable; people are more easily infected when pollution is high; public spending in health care and public debt can be used to tackle the effects of epidemics. We show that fiscal policies can promote convergence to a stable disease-free steady state. When public policies are not able to permanently eradicate the epidemic, public debt, and income transfers could reduce the number of infected people and increase capital and GDP per capita. As a prerequisite, pollution intensity should not be too high. Finally, we define a household subsidy policy that eliminates income and welfare inequalities between healthy and infected individuals.

The Macroeconomic Impact of the 1918-19 Influenza Pandemic in SwedenJournal articleMartin Karlsson, Mykhailo Matvieiev and Maksym Obrizan, B E JOURNAL OF MACROECONOMICS, Volume 23, Issue 2, pp. 637-675, Forthcoming

In this paper, we develop an overlapping generations model with endogenous fertility and calibrate it to the Swedish historical data in order to estimate the economic cost of the 1918-19 influenza pandemic. The model identifies survivors from younger cohorts as main benefactors of the windfall bequests following the influenza mortality shock. We also show that the general equilibrium effects of the pandemic reveal themselves over the wage channel rather than the interest rate, fertility or labor supply channels. Finally, we demonstrate that the influenza mortality shock becomes persistent, driving the aggregate variables to lower steady states which costs the economy 1.819% of the output loss over the next century.

Random Informative Advertising with Vertically Differentiated ProductsJournal articleRim Lahmandi-Ayed and Didier Laussel, Games, Volume 15, Issue 2, pp. 10, Forthcoming

We study a simple model in which two vertically differentiated firms compete in prices and mass advertising on an initially uninformed market. Consumers differ in their preference for quality. There is an upper bound on prices since consumers cannot spend more on the good than a fixed amount (say, their income). Depending on this income and on the ratio between the advertising cost and quality differential (relative advertising cost), either there is no equilibrium in pure strategies or there exists one of the following three types: (1) an interior equilibrium, where both firms have positive natural markets and charge prices lower than the consumer’s income; (2) a constrained interior equilibrium, where both firms have positive natural markets, and the high-quality firm charges the consumer’s income or (3) a corner equilibrium, where the low-quality firm has no natural market selling only to uninformed customers. We show that no corner equilibrium exists in which the high-quality firm would have a null natural market. At an equilibrium (whenever there exists one), the high-quality firm always advertises more, charges a higher price and makes a higher profit than the low-quality one. As the relative advertising cost goes to infinity, prices become equal and the advertising intensities converge to zero as well as the profits. Finally, the advertising intensities are, at least globally, increasing with the quality differential. Finally, in all cases, as the advertising parameter cost increases unboundedly, both prices converge increasingly towards the consumer’s income.

The determinants of political selection: a citizen-candidate model with valence signaling and incumbency advantageJournal articleSusana Peralta and Tanguy van Ypersele, INTERNATIONAL TAX AND PUBLIC FINANCE, Forthcoming

We expand the theory of politician quality in electoral democracies with citizen candidates by supposing that performance while in office sends a signal to the voters about the politician's valence. Individuals live two periods and decide to become candidates when young, trading off against type-specific private wages. The valence signal increases the reelection chances of high valence incumbents (screening mechanism of reelection), and thus their expected gain from running for office (self-selection mechanism). Since self-selection improves the average quality of challengers, voters become more demanding when evaluating the incumbent's performance. This complementarity between the self-selection and the screening mechanisms may lead to multiple equilibria. We show that more difficult and/or less variable political jobs increase the politicians' quality. Conversely, societies with more wage inequality have lower quality polities. We also show that incumbency advantage blurs the screening mechanism by giving incumbents an upper-hand in electoral competition and may wipe out the positive effect of the screening mechanism on the quality of the polity.

État des lieux de l’enseignement de l’éducation thérapeutique du patient dans la formation initiale des sages-femmes françaisesJournal articleEmilie Ohayon, Claire Marchand, David Naudin and Sébastien Riquet, Éducation thérapeutique du patient / Therapeutic patient education, Volume 15, Issue 1, pp. 10206, Forthcoming

Objectives This study aims to establish an inventory of the teaching of Therapeutic Patient Education (TPE) in the initial training of French midwives. Method: A descriptive quantitative study was conducted in France. An online questionnaire comprising 27 questions was distributed to 35 French midwifery schools. Results: Out of 19 schools that responded to the survey, 11 taught TPE, 8 did not address it in training. This teaching is mainly transversal. The obstacles to the teaching of TPE are the current density of the program, the absence of a text regulating this teaching and the difficulties in circumscribing the field of TPE in relation to that of prevention, promotion and health education. The simulation is used in only one school. Discussion: This survey shows a willingness of educational teams to invest in the teaching of health education, including TPE. For this, it is a question of strengthening the training of teachers in order to clarify the areas of intervention of the midwife calling for health promotion, prevention and health education; to offer specific internships to students and to use simulation. Extending the duration of initial training is an opportunity to plan specific teaching and to discuss the place of the health service.

Public debt as private liquidity: the Poincaré experience (1926–1929)Journal articleAurélien Espic, Financial History Review, Volume 30, Issue 3, pp. 308-329, Forthcoming

In the follow-up to the 1926 political and monetary crisis in France, a new government led by Raymond Poincaré attempted to restore monetary stability by restructuring public debt. A sinking fund was missioned to withdraw short-term public bills from money markets. This policy disorganized the largest Parisian banks of the time, as they relied on these bills to manage their liquidity. Without developed domestic money markets, no other asset could absorb the excess liquidity freed by the withdrawal of these bills, and these leading banks faced a low-rate environment. In search of yield, they expanded their activities abroad a few months before the 1929 crash. These findings renew our understanding of the expansion of France's banking sector in the 1920s. In addition, they shed new light on the role of public debt in financial stability in an open economy.