Publications

Abstract Les analyses coûts-bénéfices constituent un moyen pour le décideur public comme privé de rationaliser ses choix. Le processus semble transparent et le traitement des préférences égalitaire, puisque les préférences de chaque individu sont prises en compte de façon similaire lors de l’agrégation. Toutefois, en présence de composantes non marchandes évaluées sur la base des préférences de la population, les individus sont limités dans l’expression de leurs préférences, à la fois par leur revenu et par leur besoin de subsistance. Nous étudions les conséquences de ces contraintes sur la révélation des préférences et sur l’évaluation monétaire des biens non marchands. Nous trouvons qu’elles amènent à favoriser implicitement les préférences des individus à revenu élevé. Se pose alors la question de la correction des évaluations monétaires lors du traitement des préférences individuelles.
Keywords Economics, Health policy, Environmental policy, Consumer preference, Environment and public health
Publication HAL Google Scholar
Abstract Economic growth in advanced countries has slowed in successive stages since the 1970s and, since the crisis, has fallen to a historical low compared with the 20th century. This slowdown is mainly attributable to weaker growth in total factor productivity. In emerging countries, the situation varies: in some countries, such as South Korea and Chile, GDP per capita have been converging for several decades; in others, such as Argentina, Brazil and Mexico, relative GDP per capita has stagnated or even declined. While weak long-term growth in these latter countries can be attributed to a lack of appropriate institutions, the widespread slowdown observed in advanced countries is more difficult to interpret. One possible explanation that we explore is the decline in real interest rates since the 1990s. A circular relationship appears to exist between interest rates and productivity: productivity determines long-term returns on capital and thereby interest rates; interest rates in turn determine the minimum productivity expected from investment projects. The decline in real interest rates, which is in part attributable to demographic factors, may have led to a slowdown in productivity by making an increasing number of unproductive companies and projects profitable. We illustrate this circular relationship using a cross-country panel regression. One way of breaking out of the circular relationship would be via a new technological revolution linked to the digital economy, or, in countries where there is still room for convergence, via structural reforms to improve the diffusion of Information and Communication Technologies (ICT).
Keywords Growth, Total factor productivity, Real interest rates, Digital economy
Publication HAL Google Scholar
Abstract In their efforts to affect regulations, firms have developed specific strategies to exploit scientific uncertainty. They have manufactured doubt by hiring and funding dissenting scientists, by producing and publicizing favorable scientific findings and by generally concealing their involvement in biased research. We propose a new model to study the interplay between scientific uncertainty, firms' miscommunication and public policies. The government is benevolent but populist, and maximizes social welfare as perceived by citizens. The industry can produce costly reports showing that its activity is not harmful. Citizens are unaware of the industry's miscommunication. We first characterize the industry's optimal miscommunication policy. The industry notably ceases miscommunicating abruptly when scientists' belief reaches a critical threshold. We identify a natural condition under which miscommunication is stronger under a tax on emissions than under command and control. We then analyze research funding. A populist government may support research to enable firms to falsely reassure citizens. Establishing an independent research agency helps limit the welfare losses induced by populist policies.
Keywords Populist Policies, Environmental Policy Instruments, Scientific Uncertainty, Research Funding
Publication HAL Google Scholar
Abstract Our new approach to mobility measurement involves separating out the valuation of positions in terms of individual status (using income, social rank, or other criteria) from the issue of movement between positions. The quantification of movement is addressed using a general concept of distance between positions and a parsimonious set of axioms that characterize the distance concept and yield a class of aggregative indices. This class of indices induces a superclass of mobility measures over the different status concepts consistent with the same underlying data. We investigate the statistical inference of mobility indices using two well‐known status concepts, related to income mobility and rank mobility. We also show how our superclass provides a more consistent and intuitive approach to mobility, in contrast to other measures in the literature, and illustrate its performance using recent data from China.
Keywords Measurement axiomatic approach, Rank mobility, Income mobility
Publication HAL Google Scholar
Abstract This study investigates the empirical association of oil prices with economic activity in developed open economy namely: The United States by using the wavelet transform framework. This methodology enables the decomposition of time-series at different time-frequencies. In this study, we have used maximal overlap discrete wavelet transform, wavelet covariance, wavelet correlation, continuous wavelet power spectrum, wavelet coherence spectrum and wavelet based Granger causality approaches to analyze the relationship between oil prices and economic activity. The present study uses month frequency data for the period of 1979M1-2013M7. The results indicate that oil prices have positive impact on economic activity and the feedback effect exists between oil prices and economic activity.
Keywords Discrete wavelet analysis, Wavelet coherence, Oil prices, Economic activity
Publication HAL Google Scholar
Abstract This paper proposes a new model with time-varying slope coefficients. Our model, called CHAR, is a Cholesky-GARCH model, based on the Cholesky decomposition of the conditional variance matrix introduced by Pourahmadi (1999) in the context of longitudinal data. We derive stationarity and invertibility conditions and prove consistency and asymptotic normality of the Full and equation-by-equation QML estimators of this model. We then show that this class of models is useful to estimate conditional betas and compare it to the approach proposed by Engle (2016). Finally, we use real data in a portfolio and risk management exercise. We find that the CHAR model outperforms a model with constant betas as well as the dynamic conditional beta model of Engle (2016).
Keywords Covariance, Conditional betas, Multivariate-GARCH
Publication HAL Google Scholar