Publications

Résumé Salience theory relies on the assumption that not only the marginal distribution of lotteries, butalso the correlation of payoffs across states impacts choices. Recent experimental studies on saliencetheory seem to provide evidence in favor of such correlation effects. However, these studies failto control for event-splitting effects (ESE). In this paper, we seek to disentangle the role of corre-lation and event-splitting in two settings: 1) the common consequence Allais paradox as studiedby Bordalo et al. (2012), Bruhin et al. (2022), and Frydman and Mormann (2018); 2) choicesbetween Mao pairs as studied by Dertwinkel-Kalt and K¨oster (2020). In both settings, we findevidence suggesting that recent findings supporting correlation effects are largely driven by ESE.Once controlling for ESE, we find no consistent evidence for correlation effects. Our results thusshed doubt on the validity of salience theory in describing risky behavior.
Mots clés Salience, Event-splitting, Probability weighting, Concordance, Experiment
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Résumé We show that least-squares cross-validation methods share a common structure that has an explicit asymptotic solution, when the chosen kernel is asymptotically separable in bandwidth and data. For density estimation with a multivariate Student-t(ν) kernel, the cross-validation criterion becomes asymptotically equivalent to a polynomial of only three terms. Our bandwidth formulae are simple and noniterative, thus leading to very fast computations, their integrated squared-error dominates traditional cross-validation implementations, they alleviate the notorious sample variability of cross-validation and overcome its breakdown in the case of repeated observations. We illustrate our method with univariate and bivariate applications, of density estimation and nonparametric regressions, to a large dataset of Michigan State University academic wages and experience.
Mots clés Nonparametric density estimation, Explicit analytical solution, Cross-validation, Bandwidth choice, Academic wage distribution
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Résumé We propose Fieller-type methods for inference on generalized entropy inequality indices in the context of the two-sample problem which covers testing the statistical significance of the difference in indices, and the construction of a confidence set for this difference. In addition to irregularities arising from thick distributional tails, standard inference procedures are prone to identification problems because of the ratio transformation that defines the considered indices. Simulation results show that our proposed method outperforms existing counterparts including simulation-based permutation methods and results are robust to different assumptions about the shape of the null distributions. Improvements are most notable for indices that put more weight on the right tail of the distribution and for sample sizes that match macroeconomic type inequality analysis. While irregularities arising from the right tail have long been documented, we find that left tail irregularities are equally important in explaining the failure of standard inference methods. We apply our proposed method to analyze income per-capita inequality across U.S. states and non-OECD countries. Empirical results illustrate how Fieller-based confidence sets can: (i) differ consequentially from available ones leading to conflicts in test decisions, and (ii) reveal prohibitive estimation uncertainty in the form of unbounded outcomes which serve as proper warning against flawed interpretations of statistical tests.
Mots clés Inequality, Generalized entropy, Two samples, Fieller, Identification-robust
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Résumé Abstract Some complex models are frequently employed to describe physical and mechanical phenomena. In this setting, we have an input in a general space, and an output where is a very complicated function, whose computational cost for every new input is very high, and may be also very expensive. We are given two sets of observations of , and of different sizes such that only is available. We tackle the problem of selecting a subset of smaller size on which to run the complex model , and such that the empirical distribution of is close to that of . We suggest three algorithms to solve this problem and show their efficiency using simulated datasets and the Airfoil self‐noise data set.
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Résumé This paper investigates the dynamic effects of weather shocks on monthly agricultural production in Peru, using a Local Projection framework. An adverse weather shock, measured by an excess of heat or rain, always generates a delayed negative downturn in agricultural production. The magnitude and duration of this downturn depend on several factors, including the type of crop and the timing of the shock. On average, a weather shock—a temperature shock—can cause a monthly decline of 5% to 15% in agricultural production. The response exhibit important heterogeneity across time, crop, and season dimensions, with hysteresis suggesting farmers’ adaptation over time. At the macroeconomic level, weather shocks are recessionary and entail a decline in inflation, agricultural production, exports, exchange rate and GDP.
Mots clés Weather shocks, Agriculture, Local projections, VAR
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Résumé This paper presents a classroom experiment on the Traveler's Dilemma in order to show the impact of the common knowledge of the value of the luggage. This value becomes a focal point that canalizes the behavior of the students. This leads us to commenting on the impact of such focal points both on the reasoning of the players and on the structure of the game. We construct a new game which models this impact and we study its Nash equilibrium.
Mots clés Honesty, Classroom experiment, Focal point, Nash equilibrium, Traveler&#039, s dilemma, Dilemme du voyageur, Equilibre de Nash, Point focal, Expérience en classe, Honnêteté
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Résumé Background: Sexual and gender diverse people face intersecting factors affecting their well-being and livelihood. These include homophobic reactions, stigma or discrimination at the workplace and in healthcare facilities, economic vulnerability, lack of social support, and HIV. This study aimed to examine the association between such factors and symptoms of anxiety and depression among sexual and gender diverse people. Methods: This study is based on a sample of 108,389 gay, bisexual, queer and questioning men, and transfeminine people from 161 countries collected through a cross-sectional internet survey. We developed a multinomial logistic regression for each group to study the associations of the above factors at different severity scores for anxiety and depression symptoms. Results: Almost a third (30.3%) of the participants reported experiencing moderate to severe symptoms of anxiety and depression. Higher severity scores were found for transfeminine people (39%), and queer or questioning people (34.8%). Severe symptoms of anxiety and depression were strongly correlated with economic hardship for all groups. Compared to those who are HIV-negative, those living with HIV were more likely to report severe symptoms of anxiety and depression, and the highest score was among those who do not know their HIV status. Transfeminine people were the most exposed group, with more than 80% higher risk for those living with HIV suffering from anxiety and depression. Finally, homophobic reactions were strongly associated with anxiety and depression. The relative risk of severe anxiety and depression was 3.47 times higher for transfeminine people facing transphobic reactions than those with no symptoms. Moreover, anxiety and depression correlate with stigma or discrimination in the workplace and healthcare facilities. Conclusions: The strong association between the severity of anxiety and depression, and socioeconomic inequality and HIV status highlights the need for concrete actions to meet the United Nations' pledge to end inequalities faced by communities and people affected by HIV. Moreover, the association between stigma or discrimination and anxiety and depression among sexual and gender diverse people is alarming. There is a need for bold structural public health interventions, particularly for transfeminine, queer and questioning people who represent three communities under the radar of national HIV programmes.
Mots clés PHQ-4, Stigma and discrimination, Homophobia, HIV, Anxiety, Depression, Queer, Transgender, Bisexual, Gay, LGBT
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Résumé This paper develops a search and matching framework in which workers are characterised by asymmetric reference-dependent reciprocity, and firms set wages by considering the effect that these can have on workers' effort, and therefore on output. The cyclical response of effort to wage changes can considerably amplify shocks, independently of the cyclicality of the hiring wage, which becomes irrelevant for unemployment volatility; and firms' expectations of downward wage rigidity in existing jobs increases the volatility of job creation. The model is consistent with evidence on hiring and incumbents' wage cyclicality, and provides novel predictions on the dynamics of effort.
Mots clés Reciprocity, Wage cyclicality, Downward wage rigidity, Job creation, Unemployment volatility
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Résumé This paper introduces an autoregressive conditional beta (ACB) model that allows regressions with dynamic betas (or slope coefficients) and residuals with GARCH conditional volatility. The model fits in the (quasi) score-driven approach recently proposed in the literature, and it is semi-parametric in the sense that the distributions of the innovations are not necessarily specified. The time-varying betas are allowed to depend on past shocks and exogenous variables. We establish the existence of a stationary solution for the ACB model, the invertibility of the score-driven filter for the time-varying betas, and the asymptotic properties of one-step and multistep QMLEs for the new ACB model. The finite sample properties of these estimators are studied by means of an extensive Monte Carlo study. Finally, we also propose a strategy to test for the constancy of the conditional betas. In a financial application, we find evidence for time-varying conditional betas and highlight the empirical relevance of the ACB model in a portfolio and risk management empirical exercise.
Mots clés Betas, GARCH model, Time-varying parameters, Score driven model
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Résumé Objectives: We propose a general framework for estimating long-term health and economic effects that takes into account four time-related aspects.We apply it to a reduction in exposure to air pollution in the Canton of Geneva. Study design: Methodological developments on the evaluation of long-term economic and health benefits, with an empirical illustration. Methods: We propose a unified frameworkdthe comprehensive impact assessment (CIA)dto assess the long-term effects of morbidity and mortality in health and economic terms. This framework takes full account of four time-related issues: cessation lag, policy/technical implementation timeframe, discounting and time horizon. We compare its results with those obtained from standard quantitative health impact assessment (QHIA) in an empirical illustration involving air pollution reduction in the canton of Geneva. Results: We find that by neglecting time issues, the QHIA estimates greater health and economic benefits than the CIA. The overestimation is about 50% under reasonable assumptions and increases ceteris paribus with the magnitude of the cessation lag and the discount factor. It decreases both with the time horizon and with the implementation timeframe. Conclusion: A proper evaluation of long-term health and economic effects is an important issue when they are to be used in cost-benefit analyses, particularly for mortality, which often represents the largest fraction. We recommend using the CIA to calculate more accurate values.
Mots clés Long-term health effects, Switzerland, Economic assessment, Air pollution, Comprehensive impact assessment, Quantitative health impact assessment
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Résumé This paper develops an overlapping generations model that links a public health system to a pay-as-you-go (PAYG) pension system. It relies on two assumptions. First, the health system directly finances curative health spending on the elderly. Second, public pensions partially depend on health status by introducing a component indexed to society’s average level of old-age disability. Reducing the average disability rate in the economy then lowers pension benefits as the need to finance long-term care services also drops. We study the effects of introducing such a ‘comprehensive’ Social Security system on individual decisions, capital accumulation, and welfare. We first show that health investments can boost savings and capital accumulation under certain conditions. Second, if individuals are sufficiently concerned with their health when old, it is optimal to introduce a health-dependent pension system, as this will raise social welfare compared to a system where pensions are not tied to the society’s average level of old-age disability. Our analysis thus highlights an important policy recommendation: making PAYG pension schemes partially health-dependent can be beneficial to society.
Mots clés Long-term care, Overlapping generations, Disability, PAYG Pension System, Curative Health Investments
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Résumé La logique voudrait que Ricoeur se livre à une critique acerbe tant la conception dialectique de la justice qu'il défend, et conformément à laquelle le bon englobe le juste, s'oppose à la conception purement procédurale de Rawls. Pourtant, Ricoeur insiste sur l'extrême intérêt qu'il porte à « l'ouvrage immense de Rawls ». Ricoeur situe le projet rawlsien dans la dialectique de la justice, et le rapporte à l'un des moments de cette dialectique, à savoir le moment moral. Mais, l'enjeu majeur du commentaire de Ricoeur est plus large : il consiste à mettre l'accent sur le contenu aporétique du juste, lequel est pris « entre le légal et le bon ». L'aporie prend la forme, dans l'approche ricoeurienne de la justice sociale, de trois paradoxes : le paradoxe de la justice politique, le paradoxe de la justice juridique et le paradoxe de la justice socio-économique. Face à ces paradoxes, le projet rawlsien développé́ dans Théorie de la justice révèle à la fois ses forces et ses limites.
Mots clés Justice sociale, Équité, Universalité, Ricoeur, Rawls
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Résumé What is the role of income polarization for explaining differentials in public funding of education? To answer this question, we provide a new theoretical modelling for the income distribution that can directly monitor income polarization. It leads to a new income polarization index where the middle class is represented by an interval. We implement this distribution in a political economy model with endogenous fertility and public/private educational choices. We show that when households vote on public schooling expenditures, polarization matters for explaining disparities in public education funding across communities. Using micro-data covering two groups of school districts, we find that both income polarization and income inequality affect public school funding with opposite signs whether there exist a Tax Limitation Expenditure (TLE) or not.
Mots clés Education politics, Schooling choice, Income polarization, Probabilistic voting, Bayesian inference
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Résumé Entrepreneurship, growth and total factor productivity are larger when asset prices are high and decline during financial crises. We explain these facts using a growth model with financial bubbles in which individuals have heterogeneous wages and returns on productive investment. Heterogeneity separates individuals between savers and entrepreneurs. Savers buy financial assets, which are deposits or a financial bubble. Entrepreneurs incur in a start-up cost and borrow to invest in productive capital. The bubble provides liquidities to credit-constrained entrepreneurs. These liquidities increase investment, growth and entrepreneurship. Finally, the bubble may increase productivity when the return of each entrepreneur's investment is positively correlated with her previous income.
Mots clés Growth, Productivity, Entrepreneurship, Bubble
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Résumé Worrisome topics, such as climate change, economic crises, or pandemics including Covid-19, are increasingly present and pervasive due to digital media and social networks. Do worries triggered by such topics affect the cognitive capacities of young adults? In an online experiment during the Covid-19 pandemic (N=1503), we test how the cognitive performance of university students responds when exposed to topics discussing (i) current adverse mental health consequences of social restrictions or (ii) future labor market hardships linked to the economic contraction. Moreover, we study how such a response is affected by a performance goal. We find that the labor market topic increases cognitive performance when it is motivated by a goal, consistent with a 'tunneling effect' of scarcity or a positive stress effect. However, we show that the positive reaction is mainly concentrated among students with larger financial and social resources, pointing to an inequality-widening mechanism. Conversely, we find limited support for a negative stress effect or a 'cognitive load effect' of scarcity, as the mental health topic has a negative but insignificant average effect on cognitive performance. Yet, there is a negative response among psychologically vulnerable individuals when the payout is not conditioned on reaching a goal.
Mots clés Human behaviour, Psychology and behaviour
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Résumé Mexican cities along the US-Mexico border, especially Cd. Juarez, became notorious due to high femicide rates supposedly associated with maquiladora industries and the NAFTA. Nonetheless, statistical evaluation of data from 1990 to 2012 shows that their rates are consistent with other Mexican cities’ rates and tend to fall with increased employment opportunities in maquiladoras. Femicide rates in Cd. Juarez are in most years like rates in Cd. Chihuahua and Ensenada and, as a share of overall homicide rates, are lower than in most cities evaluated. These results challenge conventional wisdom and most of the literature on the subject.
Mots clés Maquiladoras, Crime, Gender violence, Violence against women, Homicide, Femicide, Border, Mexico, Juarez
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Résumé This paper highlights how technology can contribute to reaching the 2015 Paris Agreement goals of net zero carbon dioxide (CO2) emissions and global warming below 2°C in 2100. It uses the Advanced Climate Change Long-term model (ACCL), particularly adapted to quantify the consequences of energy price and technology shocks on CO2 emissions, temperature, climate damage and Gross Domestic Product (GDP). The simulations show that without climate policies the warming may be +5°C in 2100, with considerable climate damage. An acceleration in ‘usual’ technical progress not targeted at reducing CO2- even worsens global warming and climate damage. According to our estimates, the world does not achieve climate goals in 2100 without ‘green’ technologies. Intervening only via energy prices, e.g. a carbon tax, requires challenging hypotheses of international coordination and price increase for polluting energies. We assess a multi-lever climate strategy combining energy efficiency gains, carbon sequestration, and a decrease of 3% per year in the relative price of ‘clean’ electricity with a 1 to 1.5% annual rise in the relative price of polluting energy sources. None of these components alone is sufficient to reach climate objectives. Our last and most important finding is that our composite scenario achieves the climate goals.
Mots clés Climate, Global warming, Technology, Environmental policy, Growth, Long-term projections
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Résumé Local proximal point algorithms with quasi distances to find critical points (or minimizer points in the convex case) of functions in finite dimensional Riemannian manifolds are introduced. We prove that bounded sequences of the algorithm generated by proper bounded from below, lower semicontinuous and locally Lipschitz functions have accumulation points which are critical points (minimizer points in the convex case). Moreover, for KurdykaLojasiewicz functions, the sequence globally converges to a critical point. We applied the algorithm to a behavioral traveler’s problem where an individual tries to satisfy locally his needs and desires by moving from one city to the next, with costs to move playing a major role.
Mots clés Local search, Proximal algorithms, Riemannian manifolds, The behavioral traveler’s problem
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Résumé To what extent protectionism affects growth and (de)stabilizes the economies? Although the impact of protectionism on growth has been widely explored without reaching a consensus, few has been said on its impact on macroeconomic stability. The present paper attempts to gauge more precisely its implications using a Barro-type (Barro, 1990) endogenous growth model with public debt and credit constraint where tariffs are a proxy of protectionism. Our main result is to show that when the debt level is high, and the share of foreign goods in total consumption is large enough, increasing tariffs may have a destabilizing effect generating some expectation coordination failures between multiple equilibria. We also exhibit some trade-off between tariffs and growth as tariffs are beneficial only to the low growth equilibrium which may only appear when the international interest rate is low enough. Finally, focusing on the local stability property, we show that the high BGP is always characterized by local indeterminacy, while the low BGP is always a saddle point. We then prove that tariffs may be responsible for the existence of large self-fulfilling fluctuations.
Mots clés Public debt, Tariffs, Small open economy, Credit constraint, Global and local indeterminacy
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Résumé Lower tariffs typically raise productivity, production, and trade, increasing the benefits from building infrastructure. Infrastructure spending by governments should therefore increase after countries open up to trade. I test this hypothesis empirically using a trade reform in India and find that a 1 percentage point reduction in tariffs in- creased states’ infrastructure spending by 0.5% between 1991 and 2001. To understand the mechanisms behind my empirical findings, I develop and calibrate a multi-region model of international trade, private capital accumulation, and infrastructure spending, in which each government chooses such spending to maximize their state’s welfare. I find if governments choose infrastructure following the reform optimally, infrastructure would have increased by 60% on average. The actual increase, based on my empirical findings, was about 29%. Counterfactual exercises show that raising aggregate infras- tructure towards its optimal following the trade reform will result in state GDP to increase by 7% points on average.
Mots clés Infrastructures, Tariffs, Trade
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