Publications
Knightian uncertainty represents a situation in which it is no longer possible to form expectations about future events. We propose a method to directly measure Knightian uncertainty. Our approach relies on firm-level data and measures the share of firms that do not formalize expectations about their future demand. We construct the Knightian Uncertainty Indicator for Switzerland and show that the indicator is able to identify times of high uncertainty. We evaluate the indicator by comparing it to established uncertainty measures. We find that a one standard deviation innovation of the Knightian Uncertainty Indicator leads to a negative and persistent reduction of investment.
La part de l’aide humanitaire croît dans l’aide totale. Or les acteurs impliqués restent peu étudiés. Cet article documente la fragmentation de l’aide à un double niveau : celui des donneurs et celui des acteurs de terrains. Le jeu de délégation entre les deux peut réduire les effets négatifs de la fragmentation de l’aide. À partir de trois études de cas, le lien entre fragmentation, délégation et efficacité de l’aide humanitaire est illustré et les coûts et bénéfices potentiels de la délégation et de la fragmentation discutés.
Self-assessed health (SAH) is a widely used tool to estimate population health. However, the debate continues as to what exactly this ubiquitous measure of social science research means for policy conclusions. This study is aimed at understanding the tenability of the construct of SAH by simultaneously modelling SAH and clinical morbidity. Using data from 17 waves (2001–2017) of the Russian Longitudinal Monitoring Survey, which captures repeated response for SAH and frequently updates information on clinical morbidity, we operationalise a recursive semi-ordered probit model. Our approach allows for the estimation of the distributional effect of clinical morbidity on perceived health. This study establishes the superiority of inferences from the recursive model. We illustrated the model use for examining the endogeneity problem of perceived health for SAH, contributing to population health research and public policy development, in particular, towards the organisation of health systems.
This paper investigates whether political connections affect individuals’ propensity to engage in white-collar crime. We identify connections by campaign donations or direct friendships and use the 2007 French Presidential election as a marker of change in the value of political connections to the winning candidate. We compare the behavior of Directors of publicly listed companies who were connected to the future President to the behavior of other non-connected Directors, before and after the election. Consistent with the belief that connections to a powerful politician can protect someone from prosecution or punishment, we uncover indirect evidence that connected Directors are more likely to engage in suspicious insider trading after the election: Purchases by connected Directors trigger larger abnormal returns, connected Directors are less likely to comply with trading disclosure requirements in a timely fashion, and connected Directors trade closer in time to their firms’ announcements of results. (JEL: D72, G14, G18, G38, K22, K42)
The Southern Mediterranean region faces different environmental problems such as water scarcity, arable land depletion, air pollution, inadequate waste management, loss of biodiversity, declining marine resources, and degradation of coastal ecosystems. Despite the significant impact of these threats on the quality of life of the population, they are still not consistently part of the development strategies. South Med public policies are predominantly focused on salient threats to socio-economic development such as high unemployment (especially youth unemployment), poverty, income inequality, limited intergenerational mobility, food insecurity, political instability, and military and social conflicts. Current situation limits public policy in implementing widespread environmental instruments requiring alternative approaches. Among the latter, promising solution is offered by GreenTech startups, ecological initiatives that often take the form of small- and medium or social enterprises. They belong to a bottom-up approach where businesses are implemented as a response to current local needs of the society. Despite the high potential of this approach, it develops relatively slowly facing certain constraints due to limits of public policy. This brief focuses on the contribution of GreenTech start-ups to sustainable economic development in South Med countries. It provides an overview of the current opportunities for environmental innovations in South Med countries and the corresponding role of public policy. Then it explores the main refraining obstacles highlighting the experience of three start-ups from Lebanon, Jordan, and Tunisia working in the GreenTech field with a focus on waste and water management and apparel industries, main drivers of their growth, and challenges they are facing. Finally, it concludes with some recommendations to improve the existing public Green Tech Start-ups: Effective Solution to Sustainable Challenges in the South Med
In this paper, we consider an abstract optimal control problem with state constraint. The methodology relies on the employment of the classical dynamic programming tool considered in the infinite dimensional context. We are able to identify a closed-form solution to the induced Hamilton-Jacobi-Bellman (HJB) equation in infinite dimension and to prove a verification theorem, also providing the optimal control in closed loop form. The abstract problem can be seen an abstract formulation of a PDE optimal control problem and is motivated by an economic application in the context of continuous spatiotemporal growth models with capital di usion, where a social planner chooses the optimal location of economic activity across space by maximization of an utilitarian social welfare function. From the economic point of view, we generalize previous works by considering a continuum of social welfare functions ranging from Benthamite to Millian functions. We prove that the Benthamite case is the unique case for which the optimal stationary detrended consumption spatial distribution is uniform. Interestingly enough, we also find that as the social welfare function gets closer to the Millian case, the optimal spatiotemporal dynamics amplify the typical neoclassical dilution population size effect, even in the long-run.
This paper proposes two dominance criteria for evaluating education systems described as joint distributions of the pupils’ cognitive skill achievements and family backgrounds. The first criterion is the smallest transitive ranking of education systems compatible with three elementary principles. The first principle requires the favorable recording of any improvement in the cognitive skill of a child with a given family background . The second principle demands that any child’s cognitive skill be all the more favourably appraised as the child is coming from an unfavourable background. The third principle states that when two different skills and family backgrounds are allocated between two children, it is preferable that the high skill be given to the low background child than the other way around. Our second criterion adds to the three principles the elitist requirement that a mean-preserving spread in the skills of two children with the same background be recorded favorably. We apply our criteria to the ranking of education systems of 43 countries, where we measure cognitive skills by PISA score in mathematics and famly background by the largest of the two parents’International Socio Economic Index. Our criteria conclusively compare about 19% of all the possible pairs of countries.
This study examines a specific class of common-pool resources whereby rivalry is not characterized by competition for the resource stock. Artesian aquifers are a typical example of such resources since the stock never depletes, even when part of the resource is extracted. We first propose a dynamic model to account for the relevant features of such aquifers such as the water pressure and well yield and characterize the corresponding dynamics. We then compare the social optimum with the private exploitation of an open-access aquifer. The comparison of these two equilibria highlights the existence of a new source of inefficiency. In the long run, this so-called pressure externality results in an additional number of wells for the same water consumption, thereby raising costs. Finally, we characterize a specific stock-dependent tax to neutralize the pressure externality.
Online surveys of health professionals have become increasingly popular during the COVID-19 crisis because of their ease, speed of implementation, and low cost. This article leverages an online survey of general practitioners’ (GPs’) attitudes toward the soon-to-be-available COVID-19 vaccines, implemented in October–November 2020 (before the COVID-19 vaccines were authorized in France), to study the evolution of the distribution of their demographic and professional characteristics and opinions about these vaccines, as the survey fieldwork progressed, as reminders were sent out to encourage them to participate. Focusing on the analysis of the potential determinants of COVID-19 vaccine acceptance, we also tested if factors related to survey participation biased the association estimates. Our results show that online surveys of health professionals may be subject to significant selection bias that can have a significant impact on estimates of the prevalence of some of these professionals’ behavioral, opinion, or attitude variables. Our results also highlight the effectiveness of reminder strategies in reaching hard-to-reach professionals and reducing these biases. Finally, they indicate that weighting for nonparticipation remains indispensable and that methods exist for testing (and correcting) selection biases.
Akin to other developing countries, Algeria has witnessed an increasing role of the private health sector in the past two decades. Our study sheds light on the public–private overlap and the phenomenon of physician dual practice in the provision of health care services using the particular case of cesarean deliveries in Algeria. Existing studies have reported that, compared to the public sector, delivering in a private health facility increases the risk of enduring a cesarean section. While confirming this result for the case of Algeria, our study also reveals the existence of public–private differentials in the effect of medical variables on the probability of cesarean delivery. After controlling for selection in both sectors, we show that cesarean deliveries in the private sector tend to be less medically justified compared with those taking place in the public sector, thus, potentially leading to maternal and neonatal health problems. As elsewhere, the contribution of the private health sector to the unmet need for health care in Algeria hinges on an appropriate legal framework that better coordinates the activities of the two sectors and reinforces their complementarity.
