Publications
This paper proposes a new methodological approach using high-frequency data and local projections to assess the impact of weather on agricultural production. Local projections capture both immediate and delayed effects across crop types and growth stages, while providing early warnings for food shortages. Adverse weather shocks, such as excess heat or rain, consistently lead to delayed downturns in production, with heterogeneous effects across time, crops, and seasons. We build a new index of aggregate weather shocks that accounts for the typical delay between event occurrence and economic recognition, finding that these shocks are recessionary at the macroeconomic level, reducing inflation, production, exports and exchange rates.
« Chacun peut être amené au cours de sa vie à s’intéresser à l’histoire pour saisir les enjeux d’un affrontement entre groupes sociaux ou mieux appréhender comment les doctrines...
101 real couples participated in a controlled experimental risk-taking task involving variations in household and individual income risks, while controlling for ex-ante income inequality. Our design disentangles the effects of household risk, intra-household risk inequality, and ex-post payoff inequality. We find that most couples (about 79%) pooled their risk at the household level when risks were borne symmetrically, but a significant proportion of couples (about 36%) failed to do so when individual risks were borne asymmetrically. Additionally, within the scope of the control variables we have utilized, we find that intra-household risk inequality has a larger impact on non-married couples compared to married ones. These results remain robust when the analysis is limited to couples in which both spouses are risk-averse. Lastly, we find that preferences for household efficiency are significantly correlated across both certain and risky situations. However, couples consisting of two income-maximizing spouses do not show greater aversion to risk inequality compared to couples with other compositions.
Lack of high-quality value per statistical life (VSL) studies in low- and middle-income countries have been recognized by scholars and analysts in the benefit-cost analysis field for decades. However, progress has been slow in addressing it. We estimated VSL in China using a stated-preference survey in the context of reducing mortality risks associated with COVID-19. The survey was administered in seven cities across China in 2022 with a purposive sampling approach, and consistency checks at different levels of stringency regarding willingness to pay (WTP) for mortality risk reductions of different magnitudes were used to screen respondents. The estimated VSL ranges from 8.0 million to 10.3 million Chinese Yuan, which is higher than previous estimates. Also previous studies found much higher VSL estimates from a subsample obtained with more stringent consistency check requiring that WTP be approximately proportional to the magnitude of mortality risk reduction, we did not find such a difference with our dataset. In addition, based on our anlaysis, respondents in first-tier cities such as Beijing, Shanghai and Guangzhou have higher VSL than those in second-tier cities such as Changchun, Chengdu, Wuhan and Xi’an; the VSL-age relationship shows a U-shaped pattern; and the collective experience of city lockdown has a negative impact on VSL. Other factors which were found to influence VSL include education, sector of work, health status, risk perception, behaviors (physical exercises, wearing face masks, getting vaccinated), knowledge, political identity, and trust in government.
JEL classification codes
I12, I18
In many emerging economies with antiquated laws, bribes paid to government officials reduce economic impediments and serve as a device to improve market competition, thereby contributing to the modernization of an economy. In this context, this paper uses a simple two-stage game theoretic model to investigate the effects of the US Foreign Corrupt Practices Act (FCPA) on such economies. We demonstrate, among others, that while an increase in fines under FCPA reduces overall corruption, it leads to a deterioration in the market quality in an emerging economy. In the presence of FCPA, an increase in the US firm's technological advantage unambiguously leads to a decrease in the market quality in an emerging economy.
Many studies suggest that employees of social enterprises experience greater job satisfaction than employees of for-profit organizations, although their pay and employment contracts are usually less favorable. Based on linked employer–employee data from a French survey on employment characteristics and industrial relations and using a decomposition method developed by Gelbach (2016), this paper aims to explain this somewhat paradoxical result. Focusing on work organization variables, we show that the specific work organization of social enterprises explains a large part of the observed job satisfaction differential both in general and more specifically, in terms of satisfaction with access to training and working conditions. By detailing the components of work organization, the higher job satisfaction reported by employees in social enterprises stems from their greater autonomy and better access to information. In contrast to earlier studies, however, our results show that these work organization variables do not have more value for social enterprise employees than for for-profit organization employees in the case of overall job satisfaction. This result casts doubt on the widespread hypothesis that social enterprise employees attach more weight to the nonmonetary advantages of their work than their counterparts in for-profit organizations.
Most studies assessing animal decision-making under risk rely on probabilities that are typically larger than 10%. To study Decision-Making in uncertain conditions, we explore a novel experimental and modelling approach that aims at measuring the extent to which rats are sensitive - and how they respond - to outcomes that are both rare (probabilities smaller than 1%) and extreme in their consequences (deviations larger than 10 times the standard error). In a four-armed bandit task, stochastic gains (sugar pellets) and losses (time-out punishments) are such that extremely large - but rare - outcomes materialize or not depending on the chosen options. All rats feature both limited diversification, mixing two options out of four, and sensitivity to rare and extreme outcomes despite their infrequent occurrence, by combining options with avoidance of extreme losses (Black Swans) and exposure to extreme gains (Jackpots). Notably, this sensitivity turns out to be one-sided for the main phenotype in our sample: it features a quasi-complete avoidance of Black Swans, so as to escape extreme losses almost completely, which contrasts with an exposure to Jackpots that is partial only. The flip side of observed choices is that they entail smaller gains and larger losses in the frequent domain compared to alternatives. We have introduced sensitivity to Black Swans and Jackpots in a new class of augmented Reinforcement Learning models and we have estimated their parameters using observed choices and outcomes for each rat. Adding such specific sensitivity results in a good fit of the selected model - and simulated behaviors that are close - to behavioral observations, whereas a standard Q-Learning model without sensitivity is rejected for almost all rats. This model reproducing the main phenotype suggests that frequent outcomes are treated separately from rare and extreme ones through different weights in Decision-Making.
Over the years, oil prices and financial stock markets have always had a complex relationship. This paper analyzes the interactions and co-movements between the oil market (WTI crude oil) and two major stock markets in Europe and the US (the Euro Stoxx 50 and the SP500) for the period from 1990 to 2023. For that, I use both the time-varying and the Markov copula models. The latter one represents an extension of the former one, where the constant term of the dynamic dependence parameter is driven by a hidden two-state first-order Markov chain. It is also called the dynamic regime-switching (RS) copula model. To estimate the model, I use the inference function for margins (IFM) method together with Kim’s filter for the Markov switching process. The marginals of the returns are modeled by the GARCH and GAS models. Empirical results show that the RS copula model seems adequate to measure and evaluate the time-varying and non-linear dependence structure. Two persistent regimes of high and low dependency have been detected. There was a jump in the co-movements of both pairs during high regimes associated with instability and crises. In addition, the extreme dependence between crude oil and US/European stock markets is time-varying but also asymmetric, as indicated by the SJC copula. The correlation in the lower tail is higher than that in the upper. Hence, oil and stock returns are more closely joined and tend to co-move more closely together in bullish periods than in bearish periods. Finally, the dependence between WTI crude oil and the SP500 stock index seems to be more affected by exogenous shocks and instability than the oil and European stock markets.
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.
Background Within the International Health Regulations framework, the French High Council for Public Health was mandated in 2022 by health authorities to establish a list of priority infectious diseases for public health, surveillance and research in mainland and overseas France. Aim Our objective was to establish this list. Methods A multi-criteria decision analysis was used, as recommended by the European Centre for Disease Prevention and Control. A list of 95 entities (infectious diseases or groups of these, including the World Health Organization (WHO)-labelled ‘Disease X’) was established by 17 infectious disease experts. Ten criteria were defined to score entities: incidence rate, case fatality rate, potential for emergence and spread, impact on the individual, on society, on socially vulnerable groups, on the healthcare system, and need for new preventive tools, new curative therapies, and surveillance. Each criterion was assigned a relative weight by 77 multidisciplinary experts. For each entity, 98 physicians from various specialties rated each criterion against the entity, using a four-class Likert-type scale; the ratings were converted into numeric values with a nonlinear scale and respectively weighted to calculate the entity score. Results Fifteen entities were ranked as high-priorities, including Disease X and 14 known pathologies (e.g. haemorrhagic fevers, various respiratory viral infections, arboviral infections, multidrug-resistant bacterial infections, invasive meningococcal and pneumococcal diseases, prion diseases, rabies, and tuberculosis). Conclusion The priority entities agreed with those of the WHO in 2023; almost all were currently covered by the French surveillance and alert system. Repeating this analysis periodically would keep the list updated.
