Publications

Abstract In this paper, we tackle a generic optimal regime switching problem where the decision-making process is not the same from one regime to another. Precisely, we consider a simple model of optimal switching from competition to cooperation. To this end, we solve a two-stage optimal control problem. In the first stage, two players engage in a dynamic game with a common state variable and one control for each player. We solve for open-loop strategies with a linear state equation and linear-quadratic payoffs. More importantly, the players may also consider the possibility to switch at finite time to a cooperative regime with the associated joint optimization of the sum of the individual payoffs. Using theoretical analysis and numerical exercises, we study the optimal switching strategy from competition to cooperation. We also discuss reverse switching.
Keywords Multi-stage optimal control, Dynamic games, Competition, Cooperation
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Abstract The Pareto model is very popular in risk management, since simple analytical formulas can be derived for financial downside risk measures (value-at-risk, expected shortfall) or reinsurance premiums and related quantities (large claim index, return period). Nevertheless, in practice, distributions are (strictly) Pareto only in the tails, above (possible very) large threshold. Therefore, it could be interesting to take into account second-order behavior to provide a better fit. In this article, we present how to go from a strict Pareto model to Pareto-type distributions. We discuss inference, derive formulas for various measures and indices, and finally provide applications on insurance losses and financial risks.
Keywords EPD, Expected shortfall, Financial risks, GPD, Hill, Pareto, Quantile, Rare events, Regular variation, Reinsurance, Second order, Value-at-risk
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Abstract Currently, countries across the world are applying policies designed to combat the COVID-19 pandemic, such as lockdowns, international travel restrictions, subsectoral closures, and adjustments in public transportation. Although these restrictions can be effective in controlling the epidemiological dynamics, they also need to be assessed in terms of their acceptability by populations. The preferences of populations should matter, particularly after months of efforts, and the new requirements of lockdowns in several European countries despite these efforts.
Keywords COVID-19
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Abstract This chapter presents a survey of some recent methods used in economics and finance to account for cyclical dependence and account for their multifaced dynamics: nonlinearities, extreme events, asymmetries, non-stationarity, time-varying moments. To circumvent the caveats of the standard spectral analysis, new tools are now used based on copula spectrum, quantile spectrum and Laplace periodogram in both non-parametric and parametric contexts. The chapter presents a comprehensive overview of both theoretical and empirical issues as well as a computational approach to explain how the methods can be implemented using the R Package.
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Abstract The book is divided into two parts: The first part applies econometrics to the field of macroeconomics, discussing trend/cycle decomposition, growth analysis, monetary policy and international trade. The second part applies econometrics to a wide range of topics in financial economics, including price dynamics in equity, commodity and foreign exchange markets and portfolio analysis. The book is essential reading for scholars, students, and practitioners in government and financial institutions interested in applying recent econometric time series methods to financial and economic data.
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Abstract This paper assesses the effectiveness of risk sharing mechanisms in Europe by breaking down the factor income components into their sub-components, and aims to further examine whether financial integration and international portfolio diversification boosts or dampens risk sharing. Using a panel of European countries, we compare the years before and after the 2008 financial crisis. We extend the literature by properly taking into account the heterogeneity (in both country and time dimensions) in the panel through new econometric models. Our results show that financial income has become a major channel of risk sharing in recent years and that a higher integration in the bond and equity markets significantly improves risk sharing in the long term.
Keywords Cross-sectional dependence, Financial integration, Risk sharing, Euro area
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Abstract We investigate the link between resource revenues volatility and institutions. We build a stochastic differential game with two players (conservatives vs. liberals) lobbying for changing the institutions in their preferred directions. First, uncertainty surrounds the dynamics of institutions and the resource revenues. Second, the lobbying power is asymmetric, the conservatives’ power being increasing with resource revenues. We show the existence of a unique equilibrium in the set of affine strategies. We then examine to which extent uncertainty leads to more liberal institutions in the long run, compared to the deterministic case. We finally explore the institutional impact of volatility using a database covering 91 countries over the period 1973–2005. Focusing on financial liberalization, we find that as oil revenue volatility increases, liberalization goes down. This result is robust to different specifications and sample distinctions.
Keywords Financial liberalization policies, Stochastic dynamic games, Lobbying games, Petropolitics, Institutional dynamics
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Abstract To what extent do childhood experiences continue to affect adult wellbeing over the life course? Previous work on this link has been carried out either at one particular adult age or for some average over adulthood. We here use two British birth-cohort datasets (the 1958 NCDS and the 1970 BCS) to map out the time profile of the effect of childhood experiences on adult outcomes, including life satisfaction. We find that the effects of many aspects of childhood do not fade away over time but are rather remarkably stable. In both birth-cohorts, child non-cognitive skills are the strongest predictors of adult life satisfaction at all ages. Of these, emotional health is the strongest. Childhood cognitive performance is more important than good conduct in explaining adult life satisfaction in the earlier NCDS cohort, whereas this ranking is inverted in the more recent BCS.
Keywords Life satisfaction, Cohort data, Childhood, Adult outcomes
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