Publications

La plupart des informations présentées ci-dessous ont été récupérées via RePEc avec l'aimable autorisation de Christian Zimmermann
Competitive equilibrium cycles for small discounting in discrete-time two-sector optimal growth modelsJournal articleAlain Venditti, Studies in Nonlinear Dynamics & Econometrics, Volume 23, Issue 4, pp. 1-14, 2019

We study the existence of endogenous competitive equilibrium cycles under small discounting in a two-sector discrete-time optimal growth model. We provide precise concavity conditions on the indirect utility function leading to the existence of period-two cycles with a critical value for the discount factor that can be arbitrarily close to one. Contrary to the continuous-time case where the existence of periodic-cycles is obtained if the degree of concavity is close to zero, we show that in a discrete-time setting the driving condition does not require a close to zero degree of concavity but a symmetry of the indirect utility function’s concavity properties with respect to its two arguments.

The love for children hypothesis and the multiplicity of fertility ratesJournal articlePaolo Melindi-Ghidi et Thomas Seegmuller, Journal of Mathematical Economics, Volume 83, Issue C, pp. 89-100, 2019

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.

Country Factors and Investment Decision-Making Process of Sovereign Wealth FundsJournal articleJeanne Amar, Bertrand Candelon, Christelle Lecourt et Zhou Xun, Economic Modelling, Volume 80, pp. 34-48, 2019

We examine in this paper the complex decision-making processes that lead to investment location choice of Sovereign Wealth Funds (SWFs). Using a two-tiered dynamic Tobit panel model, we find that country-level factors do not have the same impact on the investment decision and the amount to invest and that SWFs tend to invest more frequently and with higher amounts in countries in which they already have invested. More specifically, we find that SWFs prefer to invest in countries with higher political stability, whereas they are more prone to investing for large amounts in countries that are less democratic and more financially opened. Our results also lend support to the idea that SWFs are prudent in the choice of target country concerning their investment decision but behave as more opportunistic investors concerning the amounts to be invested.

On the optimality of path-dependent structured funds: The cost of standardizationJournal articlePhilippe Bertrand et Jean-Luc Prigent, European Journal of Operational Research, Volume 277, Issue 1, pp. 333-350, 2019

This paper examines the suitability of an important class of standard financial structured products, namely those whose performances are based on smoothing the return of a given risky underlying asset while providing a guarantee at maturity. Using various assumptions about the customers attitudes towards risk, we show that such standardized products are not optimal, even if the financial market volatility is constant. As a by-product, we provide in particular the optimal portfolio value in the regret/rejoice framework to go further with the notion of aversion of getting a return smaller than the risk-free one. Using the notion of compensating variation, we determine for the first time, the monetary losses of providing these standardized products instead of the optimal ones to the customers. We show that these monetary losses can be very significant when the volatility of the risky asset is stochastic. From the operational point of view, such results highly suggest to trade on the Volatility Index (VIX) and/or to introduce derivatives written on it, when selling standardized funds in order to better meet investors needs and preferences.

Option-Based performance participationJournal articleRudi Zagst, Julia Kraus et Philippe Bertrand, Journal of Banking & Finance, Volume 105, Issue C, pp. 44-61, 2019

The purpose of this article is to introduce and analyze the option-based performance participation (OBPP) as performance participation method based on a portfolio consisting of two risky assets. By generalizing the provided guarantee to a participation in the performance of a second risky underlying, this new kind of strategies allows to cope with well-known problems associated with standard portfolio insurance methods, especially in times of low or even negative interest rates. However, the minimum guaranteed portfolio value at the end of the investment horizon is not deterministic anymore, but subject to systematic risk instead. Hence, we compare the newly introduced OBPP with the option-based portfolio insurance (OBPI) in various dimensions such as terminal payoffs, mean-variance efficiency and stochastic dominance. To do this, general analytical expressions for all moments of the payoff distributions of the two strategies are derived. Furthermore, we show how an OBBP can be designed so that it stochastically dominates a given OBPI (with a given probability) while retaining the potential for a participation in rising markets via a so-called reserve asset. Numerical case studies show how the proposed concept can be easily implemented for practical applications.

Linear Quantile Regression and Endogeneity CorrectionJournal articleChristophe Muller, Biostatistics and Biometrics Open Access Journal, Volume 9, Issue 5, pp. 1-6, 2019

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

Empirical evidence on the long and short run determinants of health expenditure in the Arab worldJournal articleKarim Barkat, Rashid Sbia et Youcef Maouchi, The Quarterly Review of Economics and Finance, Volume 73, Issue C, pp. 78-87, 2019

This paper empirically examines the determinants of health care spending for 18 Arab world countries for the period 1995–2015 by using recently developed panel cointegration techniques. We conducted the same estimations for 3 sub-samples, namely high-income, upper-middle- and lower-middle-income countries to reduce the heterogeneity among them. Our empirical findings demonstrate that health care expenditure and its determinants are non-stationary, and revealed the existence of a long run relationship among variables. Furthermore, the estimation results suggest that income is not the only driver of health expenditure in the Arab world countries in the long run. Other variables such as medical progress and ageing population are also playing an important role in the increase of health care expenditure with major policy implications for the region in the long run. Furthermore, the results support that health care expenditure is a necessity good for the three income groups. Finally, the Pairwise Dumitrescu-Hurlin panel causality test shows evidence of a bidirectional causal relationship between health care expenditures and income for the full sample, as well as for the groups income.

Un impôt immobilier tout en un : rendement, progressivité et faisabilitéJournal articleGuillaume Bérard et Alain Trannoy, Revue de l'OFCE, Volume 161, Issue 1, pp. 177-224, 2019

Nous étudions la faisabilité d’un impôt foncier unique (IFU) sur le patrimoine foncier et immobilier des ménages qui remplacerait tous les impôts existants portant sur ce type de patrimoine, en particulier, la taxe foncière, l’IFI, les DMTO, la taxe sur les plus-values immobilières et l’impôt sur les revenus fonciers perçus par les propriétaires bailleurs. La valeur du patrimoine net de la dette immobilière, moins un abattement sur la valeur de la résidence principale de 50 000 euros, serait taxée au taux de 1 % jusqu’au seuil de l’IFI (soit 1,3 million d’euros) et à hauteur de 1,5 % au-delà. Les recettes seraient partagées entre l’État et les collectivités territoriales au moyen d’un fonds de péréquation. Après avoir présenté les raisons qui légitiment notre proposition de réforme, nous procédons à une première évaluation du rendement de l’impôt et du profil de la charge fiscale en fonction du revenu, de la taille familiale et de l’âge en mobilisant l’enquête Patrimoine de l’INSEE. La décorrélation partielle des revenus et des patrimoines immobiliers permet difficilement d’en faire un grand impôt de rendement, même si la recette fiscale espérée est équivalente à la recette perdue des impôts remplacés. Un plafonnement de l’IFU en termes de revenu disponible briderait assez rapidement son rendement.

Comportements et pratiques des médecins : exercer dans les zones les moins dotées, cela fait-il une différence ?Journal articleJulien Silhol, Bruno Ventelou, Anna Zaytseva et Claire Marbot, Revue francaise des affaires sociales, Issue 2, pp. 213-249, 2019

[FR]
Selon les projections récentes, les effectifs de médecins libéraux diminueront de 30 % d’ici à 2027 et la densité standardisée diminuerait jusqu’en 2023, créant des poches de sous-densité relativement nombreuses sur le territoire français métropolitain. L’article s’intéresse aux ajustements que les médecins généralistes de ville mettent en œuvre lorsque, sur leur territoire, ils sont d’ores et déjà confrontés à cette raréfaction. Les données utilisées sont celles du troisième panel des médecins généralistes enrichies d’indicateurs fournis par la CNAMTS. Nous nous sommes appuyés sur l’indicateur d’accessibilité potentielle localisé, développé par l’IRDES et la DREES, pour définir les zones les moins dotées en généralistes. En comparant les comportements des généralistes exerçant dans les zones les moins dotées à leurs homologues des zones mieux dotées, il est apparu d’abord que le planning d’activité du médecin tend à s’intensifier plutôt qu’à s’allonger. Nos données semblent en effet montrer que les rythmes de consultation dans les zones les moins dotées sont plus élevés, alors que le temps de travail global des généralistes s’avère quant à lui peu réactif à la densité en médecins alentour. On note aussi quelques différences statistiquement significatives sur les pratiques médicales : usage accru de certains médicaments, moins de renvoi vers des soins paramédicaux, suivis gynécologique probablement un peu moins réguliers, etc. Cependant, il semble que les différences ne sont pas statistiquement significatives pour les indicateurs de qualité des pratiques rattachés au dispositif de rémunération sur objectifs de santé publique (ROSP).
[EN]
According to recent projections, the number of private practice physicians will decrease by 30 % by 2027 and the standardised density will continue to decline up to 2023, thus creating territorial inequalities in physicians’ distribution in mainland France. This article focuses on the adaptations that private general practitioners (GPs) make when they already practice in underserved areas. The data used are those of the third panel of general practitioners matched with indicators provided by the Social Security (CNAMTS). We used the local potential accessibility indicator developed by IRDES and DREES to define the underserved areas for general practitioners. Our results show that GPs’ consultation rhythm is higher in underserved areas, while the overall working-time is not very responsive to the local medical density. We also find some statistically significant differences in practices : more frequent prescription of certain drugs, less referrals to paramedical care, probably less regular gynaecological follow-up, for GPs practicing in underserved areas compared to their counterparts in better-served areas. However, it appears that there are no significant differences regarding the indicators of Rémuneration sur objectifs de santé publique (ROSP) [French supplementary payment-for-performance] program, which could allow a first assessment of the quality of care.

Gender and Promotions: Evidence from Academic Economists in FranceJournal articleClément Bosquet, Pierre-Philippe Combes et Cecilia Garcia-Peñalosa, Scandinavian Journal of Economics, Volume 121, Issue 3, pp. 1020-1053, 2019

The promotion system for French academic economists provides an interesting environment to examine the promotion gap between men and women. Promotions occur through national competitions for which we have information both on candidates and on those eligible to be candidates. Thus, we can examine the two stages of the process: application and success. Women are less likely to seek promotion, and this accounts for up to 76 percent of the promotion gap. Being a woman also reduces the probability of promotion conditional on applying, although the gender difference is not statistically significant. Our results highlight the importance of the decision to apply.