Publications

Résumé Background Efficiency analyses have been widely used in the literature to rank countries regarding their health system performances. However, little place has been given to the environmental aspect: two countries with the same characteristics could experience completely different healthcare system outcomes just because they do not face the same environmental quality situation, which is a major determinant of the health of inhabitants. Methods Using a stochastic frontier model, this paper analyses the effect of environmental quality on health system outcomes in OECD countries, measured by life expectancy at birth. Results We show that the healthcare system performance ranking of OECD countries changes significantly, depending on whether the environmental index is taken into account. Conclusions These findings, once again, underline the critical importance of the environment when addressing population health issues. In general, our results can be aligned with the messages of the One Health approach literature.
Mots clés Health, Healthcare system efficiency, Health production function, Environment, Stochastic frontier analysis, Panel data
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Résumé I present a model of optimal capital taxation where agents with heterogeneous labor productivity randomly draw their rate of return to savings. Because of scale dependence, the distribution of rates of returns can depend on the amount saved. Uncertainty in returns to savings yields an insurance rationale for taxing capital on top of labor income. I first show that, because of scale dependence, agents making the same saving decision should access the same rate of return at the optimum. I then constrain the information set of the government and show that, as soon as return are uncertain, positive capital income taxation is needed at the optimum. The optimal linear tax on capital income trades off insurance with distortions to both savings and to the rate of return in a context of scale dependence. Eventually, I argue that scale dependence in and of itself is not sufficient to justify capital taxation on top of labor income taxes. These results are still valid when agents can optimize between a risk-free and a risky-asset that can both exhibit scale dependence.
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Résumé The massive shift towards teleworking during the COVID pandemic relatively deteriorated working conditions of people occupying positions that could not be teleworked because they were more exposed to the risk of infection. Exploiting French data, we analyse the differential changes in sorting across occupations of immigrants and natives during years preceding the pandemic. Immigrants sorted relatively more into occupations intensive in non-routine manual tasks. These occupations cannot be teleworked. We find an increase in immigrants' sorting into occupations intensive in non-routine interactive and analytical tasks. However, in contrast with natives, immigrants were moving away from occupations intensively using new technologies.
Mots clés Jobs, Gender, Immigrants, Health-status, Task specialization
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Résumé Understanding the mechanisms of deforestation is necessary in order to slow or arrest its progress. To accomplish this requires rigorously estimating the demand for deforestation. We contribute to this endeavor by estimating the effect of crop prices on the demand for conversion of land from forest to agriculture in the tropics during the 21st century. The two main difficulties involved are the lack of harmonized data on local crop prices in the tropics and the fact that they are determined simultaneously with decisions to deforest. We propose a strategy to circumvent these two issues using high-resolution annual forest loss data for the tropics, combined with information on crop-specific agricultural suitability and annual international crop prices. We find that crop price variation has a significant impact on deforestation: increases in crop prices are estimated to be responsible for one-third of total deforestation in the tropics (totaling about 2 million km2) during the period 2001–2018. We also find that the degree of openness to international trade and the level of economic development are first-order local characteristics affecting the magnitude of the impact of crop prices on deforestation.
Mots clés Agricultural commodity prices, Déforestation
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Résumé Has secular education contributed to the decline of polygamy in Africa? To answer this question, we study a wave of public school construction in late-colonial Cameroon. Our difference-in-differences and event-study specifications show that school openings have simultaneously increased education and the chances to be in a polygamous union for men and, more surprisingly, for women. We estimate a structural model of marriage to explain why education made women more likely to be in a polygamous union. The main estimated channel is marriage to educated men who are more often polygamists than uneducated men, not direct preferences for polygamy.
Mots clés Polygamy, Education, Marriage, Matching models
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Résumé This paper introduces the class of quasi score-driven (QSD) models. This new class inherits and extends the basic ideas behind the development of score-driven (SD) models and addresses a number of unsolved issues in the score literature. In particular, the new class of models (i) generalizes many existing models, including SD models, (ii) disconnects the updating equation from the log-likelihood implied by the conditional density of the observations, (iii) allows testing of the assumptions behind SD models that link the updating equation of the conditional moment to the conditional density, (iv) allows QML estimation of SD models, (v) and allows explanatory variables to enter the updating equation. We establish the asymptotic properties of the QLE, QMLE and MLE of the proposed QSD model as well as the likelihood ratio and Lagrange multiplier test statistics. The finite sample properties are studied by means of an extensive Monte Carlo study. Finally, we show the empirical relevance of QSD models to estimate the conditional variance of 400 US stocks.
Mots clés Score-driven models, GARCH, Fat-tails, Asymmetry, QLE, QMLE
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Résumé We propose an inertial proximal point method for variational inclusion involving difference of two maximal monotone vector fields in Hadamard manifolds. We prove that if the sequence generated by the method is bounded, then every cluster point is a solution of the non-monotone variational inclusion. Some sufficient conditions for boundedness and full convergence of the sequence are presented. The efficiency of the method is verified by numerical experiments comparing its performance with classical versions of the method for monotone and non-monotone problems.
Mots clés Variational inclusion, Proximal point method, Monotone vector fields, DC functions, Hadamard manifolds
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Résumé Throughout our project on premodern academia, we use a heuristic human capital index to measure each scholar’s quality. This index is built by combining several statistics from individual Wikipedia and Worldcat pages. The question we address here is whether this measure is correlated with the actual wages professors received. This note is a technical appendix to our paper on the academic market (De la Croix et al. 2020) but also has an interest as a stand-alone publication. There is considerable evidence that compensations for academic contractswentwell beyond paid salaries.1 They included payments from students, prebends,2 and many forms of in-kind benefits. Yet, it is interesting to examine the relationship between scholars’ human capital and existing data on monetary remunerations. Such remunerations have been used by Dittmar (2019) to show that professor salaries increased significantly relative to skilled wages after printing spread, with science professors benefiting from the largest salary increases. In the two sections below, we first review the available data on salaries, and argue that such data are imperfect proxies for the overall remuneration for academic services (i.e. a scholar’s market value). Keeping in mind such limitations, we thendocument a positive correlation between monetary income and scholars’ human capital.
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Résumé We study price personalization in a two period duopoly with horizontally differentiated products. In the second period, a firm has collected detailed information on its old customers, using it to engage in price personalization. Customers, when returning to buy, may choose to incur a cost in order to access the standard offer of their previous provider in addition to its personalized offer and the standard offer of its rival. The analysis confirms that firms’ second period profits are boosted when consumers are active in this sense (being equal to perfect price discrimination ones when initial market hares do not differ too much) but it reveals that this advantage is dissipated and possibly over-dissipated by the resulting fierce first-period competition for the market. Two-period aggregate profits are smaller with active customers provided the consumers are naive and/or the firms patient enough. Consumers’ access to both personalized and standard firms’ offers which benefit the oligopolists in mature markets may plausibly hurt them in emergent ones. The equilibrium is shown not to depend on the level of the cost as long as it is below some critical value.
Mots clés Identity management, Active customers, Behavior-Base price discrimination
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Résumé This study investigates the effects of the investment-based presence of multinational enterprises (MNEs) on poverty in developing countries. The relationship is decomposed into different pathways corresponding to various facets of firms’ presence and activities, and monetary and multidimensional poverty. We hypothesize that depending on the pathways, the effects can be positive or negative in terms of poverty alleviation, and an overall conclusion has to be nuanced. The hypotheses are tested across 431 Indonesian administrative districts, observed in 2008, 2014 and 2018. Pooled instrumental variable regressions show that a higher presence of foreign MNEs does not reduce the number of people below the poverty line. It raises the depth and severity of poverty, and the population is also more exposed to pollutions. These results inform the ongoing debate, and offer important implications for policy makers eager to attract foreign direct investments, as well as for MNEs’ managers concerned with social responsibility and achieving sustainable development goals in host developing countries.
Mots clés Indonesia, Developing country, CSR, Poverty, FDI, Multinational enterprises
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Résumé We study how firm premia influence the gender wage gap for 21 European countries. We use a quadrennial harmonized matched employer-employee dataset to estimate gender-specific firm premia. Subsequently, we decompose the firm-specific wage premia differential into withinand between-firm components. On average, the former accounts mainly for the decline in the pay gap between 2002 and 2014. We pay particular attention to the development of each component by age group, and find that the between-firm component is associated with an increase in the gender pay gap over age. The decomposition of firm premia allows us to investigate how institutional settings relate to each component. We associate the within-firm component with collective bargaining at the national and firm levels, and the between-firm component with family policies. Decentralized wage bargaining is associated with a larger within-firm pay gap, whereas family policies incentivizing women to return to employment after family formation are linked to a smaller between-firm component.
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Résumé A common practice in many auctions is to offer bidders an opportunity to improve their bids, known as a best and final offer stage. This improved bid can depend on new information either about the asset or about the competitors. This paper examines the effects of new information regarding competitors, seeking to determine what information the auctioneer should provide assuming the set of allowable bids is discrete. The rational strategy profile that maximizes the revenue of the auctioneer is the one where each bidder makes the highest possible bid that is lower than his valuation of the item. This strategy profile is an equilibrium for a large enough number of bidders, regardless of the information released. We compare the number of bidders needed for this profile to be an equilibrium under different information structures. We find that it becomes an equilibrium with fewer bidders when less additional information is made available to the bidders regarding the competition. It follows that when the number of bidders is a priori unknown, there are some advantages to the auctioneer not revealing information and conducting a one-stage auction instead.
Mots clés Auctions, Multistage auctions, BAFO, Information utilization
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Résumé This paper constructs internationally consistent measures of macroeconomic uncertainty. Our econometric framework extracts uncertainty from revisions in data obtained from standardized national accounts. Applying our model to post-WWII real-time data, we estimate macroeconomic uncertainty for 39 countries. The cross-country dimension of our uncertainty data allows us to study the impact of uncertainty shocks under varying degrees of employment protection legislation. Our empirical findings suggest that the effects of uncertainty shocks are stronger and more persistent in countries with low employment protection compared to countries with high employment protection. These empirical findings are in line with a theoretical model under varying firing cost.
Mots clés Uncertainty shocks Real-time data, Rational forecast error, Employment protection legislation, System of national accounts
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Résumé We formulate a hydro-economic model of the North-Western Sahara Aquifer System (NWSAS) to assess the effects of intensive pumping on the groundwater stock and examine the subsequent consequences of aquifer depletion. This large system comprises multi-layer reservoirs with vertical exchanges, all exploited under open access properties. We first develop a theoretical model to account for relevant features of the NWSAS by introducing, in the standard Gisser-Sanchez model, a non-stationary demand and quadratic stock-dependent cost functions. In the second step, we calibrate parameters values using data from the NWSAS over 1955–2000. We finally simulate the time evolution of the aquifer system with exploitation under an open-access regime. We specifically examine time trajectories of the piezometric levels in the two reservoirs, the natural outlets, and the modification of water balances. We find that natural outlets of the two reservoirs might be totally dried before 2050.
Mots clés Hydro-economic model, Private pumping, Multi aquifer system, Groundwater-dependant ecosystems, Semi-arid region, Simulation
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Résumé This paper highlights the procyclical and unstable behaviour of mutual funds, characterized by a varying sensitivity on common asset pricing factors. It proposes a novel factor model that allows for regime changes associated with macroeconomic and financial state variables. Estimated on a panel covering 825 US equity mutual funds over a period of 30 years, it appears that the yield curve, the dividend yield, short term interest rates and the industrial production coincide with regimes switches in the Fama-French factors. Furthermore, the estimated regimes coincide with financial crises and economic downturns, thus confirming the procyclical behaviour of mutual funds' returns. These findings, coupled with the emerging systemic role of mutual funds, promote the consideration for a specific macroprudential regulatory framework targeted at the mutual fund industry.
Mots clés Régulation, Mutual fund industry, Macroprudential framework, Financial stability
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Résumé Que nous dit l’industrie cinématographique américaine sur le rôle économique de Wall Street et la perception de la bourse dans le temps ? À travers un corpus conséquent de films américains du XXe et XXIe siècles, cet article illustre comment, en trois périodes distinctes, Hollywood a pu mettre en scène la finance et contribuer au mythe de Wall Street. Sujet mineur jusque dans les années 1980, ces années ont vu l’apparition de blockbusters financiers avec la montée en puissance de la financiarisation de l’économie. La crise des subprimes renouvelle le genre, questionnant la place de la bourse et l’éthique des traders.
Mots clés Traders, Ethics, Movies, Finance, Wall Street, Wall Street, Cinéma, Ethique, Économie, Traders
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Résumé In many societies, parents are involved in selecting a spouse for their child, integrating this with decisions about premarital investment such as education. Do spousal preferences of parents and children conflict? We estimate parents’ spousal preferences based on survey choices between random profiles, elicited from parents or other relatives who actively search for a spouse on behalf of their adult child in Kunming, China. We simulate marriage outcomes based on preferences for age and education and compare them with patterns in the general population and with the preferences of a survey of students. The common concern that there may be aversion to highly educated or high-earning wives is somewhat corroborated in parents’ preferences but not in students’ preferences, nor in outcomes, where homogamy is common and wives who are more educated than husbands are as common as husbands who are more educated than wives. Parents prefer wives younger than their husbands, yet most couples are the same age, an outcome consistent with student preferences. Overall, divergences between parental and child preferences exist but are neither major nor very influential in explaining observed outcomes. Fears that highly educated women face diminished marriage prospects appear less serious than often claimed.
Mots clés Marriage, Preference estimation, China, Parental matchmaking, MATCHING
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Résumé Introduction Alcohol use disorder (AUD) is associated with a significant disease burden in France, where alcohol use is deeply rooted in culture. However, the treatment gap is large because of several barriers, including stigmatisation and drinkers' apprehension about total abstinence. However, standardised and evidence-based interventions based on controlled-drinking for people with AUD are lacking. We aimed to assess the effectiveness of a novel community-based French therapeutic patient education (TPE) program for people with AUD named Choizitaconso. Methods A before-after non-randomised quasi-experimental study, named ETHER, was designed and implemented with people living with AUD, over a period of 6 months. The primary outcome was percentage change in the number of alcohol-related harms experienced. Secondary outcomes were percentage changes in psycho-social patient-reported and community-validated outcomes. Participants in the intervention group (n = 34) benefited from the 10-week TPE program Choizitaconso, while the comparison group (n = 58) received standard care. The Kruskall–Wallis and chi-squared or Fisher's exact tests were used to compare before-after changes in variables in both groups. Linear regression models were used to test for the effect of study group on each outcome and to test for the effect of alcohol consumption as a confounder. Results At 6 months, all outcomes but one either remained stable or numerically improved in both groups. Internalised stigma significantly improved in the intervention group (p = 0.026) but not in the comparison group (p = 0.207), with a significant group effect (p = 0.014). Discussion and Conclusions This study demonstrates the effectiveness of the Choizitaconso TPE program on community-validated outcomes, especially internalised stigma.
Mots clés France, Alcohol use disorder, Harm reduction, Psychosocial skills, Therapeutic patient education
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Résumé In this paper we present a subgradient method with non-monotone line search for the minimization of convex functions with simple convex constraints. Different from the standard subgradient method with prefixed step sizes, the new method selects the step sizes in an adaptive way. Under mild conditions asymptotic convergence results and iteration-complexity bounds are obtained. Preliminary numerical results illustrate the relative efficiency of the proposed method.
Mots clés Subgradient method, Non-monotone line search, Convex function
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