Publications

Résumé Panel VAR methodology is used in this study to empirically evaluate the effects of natural disasters and state fragility on economic and financial dimensions in developing countries such as GDP per capita, banking and financial system deposits, banks’ Z-scores, and non-performing loans. Results based on three panels of up to 66 countries and 17 years of annual data indicate that natural disasters and state fragility may cause significant economic and financial disruption in low-income and middle-income countries. Shocks from natural disasters seem to be temporary and detrimental only to non-performing loans, while shocks from state fragility appear to be permanent and to create detrimental economic and financial feedback loops.
Mots clés State fragility, Natural disasters, GDP per capita, Banking stability
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Résumé In familiar models, a decrease in the friction facing mobile factors (e.g., lowering their adjustment costs) increases a coordination problem, leading to more circumstances where there are multiple equilibria. We show that a decrease in friction can decrease coordination problems when a production externality arises from a changing stock, e.g. of pollution or knowledge. In general, the relation between the amount of friction that mobile factors face and the likelihood of multiple equilibria is non-monotonic.
Mots clés Costs of adjustment, Multiple equilibria, Factor reallocation, Intersectoral migration, Learning-by-doing, Coordination games, Cross-sectoral pollution
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Résumé Using a simple decision-theoretic approach, we formalize how agents with different kinds of intrinsic motivations react to the introduction of monetary incentives. We contend that empirical results supporting the existence of a crowding-out effect under various legal procedures hide a more complex reality, where some individuals contribute thanks to these additional monetary incentives while others reduce their contributions. Our approach allows us to study the theoretical ability of the self selection mechanism (Mellström and Johannesson in J Eur Econ Assoc 6:845–863, 2008; Beretti et al. in Kyklos 66(1):63–77, 2013) to reduce the likelihood to backfire against the cause it is meant to promote. This mechanism consists of a monetary payment for the pro-social behavior and it offers agents the choice to either keep the money for themselves or to direct it to a charity. We show that this legal procedure dominates others more classical procedures because it taps wisely into the motivational heterogeneity of individuals. It uses a self-selection mechanism to match adequate monetary incentives with individuals’ types regarding intrinsic motivations. It may even turn a situation subject to crowding-out into a crowding-in outcome.
Mots clés Environmental Regulation, Moral motivation, Heterogeneity, Crowding-out
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Résumé Young Europeans experience high unemployment rates, job instability, and late emancipation. Meanwhile, they do not support reforms weakening protection on long-term contracts. In this paper, we suggest a possible rationale for such reform distaste. When the rental market is strongly regulated, landlords screen applicants with regard to their ability to pay the rent. Protecting regular jobs offers a second-best technology to sort workers, thereby increasing the rental market size. We provide a model where nonemployed workers demand protected jobs despite unemployment and the share of short-term jobs increases, whereas the individual risk of dismissal is unaffected. Our theory can be extended to alternative risks and markets involving correlated risks and commitment under imperfect information.
Mots clés Rent default, Screening, Labor market dualism
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Résumé In this paper, we consider competitive polluting firms that outsource their abatement activity to an upstream imperfect competitive eco-industry to comply with environmental regulation. In this case, we show that an usual environmental policy based on a Pigouvian tax or a pollution permit market reaches the first-best outcome. The main intuition is based on the idea that purchasing pollution reduction services instead of pollution abatement inputs modifies for each potential tax rate (or out of the equilibrium permit price) the nature of the arbitrage between pollution and abatement. This induces a demand for abatement services which is, at least partially, strongly elastic and therefore strongly reduces upstream market power. This argument is first illustrated with an upstream monopoly selling eco-services to a representative polluting firm under a usual Pigouvian tax. We then progressively extend the result to permit markets, heterogeneous downstream polluters and heterogeneous upstream Cournot competitors. JEL Codes: Q58, D43
Mots clés Abatement Outsourcing, Imperfect competition, Eco-industry, Environmental Regulation
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Résumé This paper studies the optimal growth path of a natural resource-rich country, which can borrow from international financial markets. I explore to what extent international borrowing can overcome resource scarcity in a small open economy, in order to have sustainable growth. First, a benchmark model with a constant interest rate and technical progress is set up to see if the economy's growth can be sustainable in the long run. Secondly, the case of a debt elastic interest rate is analysed. The main finding of this paper is that borrowing on international capital markets does not permit sustainable growth for a country with exhaustible natural resources, when the interest rate is constant. Nevertheless, when the interest rate is endogenized, the consumption growth rate can be positive before declining.
Mots clés Financial markets, Exogenous growth, Exhaustible natural resources
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Résumé We study the determination of public tuition fees through majority voting in a vertical differentiation model where agents' returns on educational investment differ and public and private universities coexist and compete in tuition fees. The private university offers higher educational quality than its competitor, incurring higher unit cost per trained student. The tuition fee for the state university is fixed by majority voting while that for the private follows from profit maximization. Then agents choose to train at the public university or the private one or to remain uneducated. The tax per head adjusts in order to balance the state budget. Because there is a private alternative, preferences for education are not single-peaked and no single-crossing condition holds. An equilibrium is shown to exist, which is one of three types: high tuition fee (the “ends” are a majority), low tuition fee (the “middle” is a majority), or mixed (votes tie). The cost structure determines which equilibrium obtains. The equilibrium tuition is either greater (majority at the ends) or smaller (majority at the middle) than the optimal one.
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Résumé We challenge the accepted wisdom of a global secular decline in the labor share. A simple theoretical model is proposed to highlight the main factors of change in the labor share. We document three issues in the existing literature: (i) starting periods for the empirical analysis; (ii) accounting for self employment; and (iii) accounting for residential real estate income. An empirical analysis is carried out since the post war period for France and the United States, and since the 1990s for ten developed countries and on a six country “euro area”. How the three questions above are addressed is crucial to the diagnosis. When the biases that may arise with the three issues mentioned above are eliminated, the labor share in the market sector does not show a general downward or upward trend. The choice of period has a huge impact, as does the treatment of real estate services, whose inclusion or not in the value added can result in significantly different trends.
Mots clés Value added sharing, Labor cost, Labor share
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Résumé This paper is devoted to new versions of Ekeland’s variational principle in set optimization with domination structure, where set optimization is an extension of vector optimization from vector-valued functions to set-valued maps using Kuroiwa’s set-less relations to compare one entire image set with another whole image set, and where domination structure is an extension of ordering cone in vector optimization; it assigns each element of the image space to its own domination set. We use Gerstewitz’s nonlinear scalarization function to convert a set-valued map into an extended real-valued function and the idea of the proof of Dancs-Hegedüs-Medvegyev’s fixed-point theorem. Our setting is applicable to dynamic processes of changing jobs in which the cost function does not satisfy the symmetry axiom of metrics and the class of set-valued maps acting from a quasimetric space into a real linear space. The obtained result is new even in simpler settings.
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Résumé The demand for weather-sensitive products, such as beverages, ice creams, or chocolate varies with changes in temperature. Yet, retailers lack a framework to adapt the marketing mix elements, such as price and advertising, in line with such changes. We provide a theoretical framework to fill this gap by developing an analytical model to derive the optimal marketing mix when product demand depends on temperature. The model prescribes how price and advertising for different demand characteristics should be set following a temperature change. Integrating the temperature element in the marketing mix offers an original profit-enhancing strategy.
Mots clés Marketing mix, Weather-sensitivity, Temperature, Advertising, Pricing
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