Travaux
- Publications dans des revues scientifiques
- Ouvrages et rapports
- Documents de travail et autres publications
- Communications
2022
Can Public Debt Mitigate Environmental Debt? Theory and Empirical Evidence
This paper investigates the relationship between public debt and environmental debt—reflecting CO carbon concentration. First, using an endogenous growth model in which pollution abatement spending can be financed by public debt, we show that public debt and environmental debt are complementary in the long run and usually substitutes in the short run. Second, these predictions are empirically confirmed: in particular, a 1% increase in the public debt ratio leads to an increase of 0.74% in cumulative CO per capita in the long run. Our findings emphasize the difficulty of defining policies that jointly serve both the economic (fiscal) and the environmental goals, due to the short- and long-run conflicting environmental effects of policies that either reduce or do not constrain public debt.
Lien HAL
Review of Charly Coleman's The Spirit of French Capitalism: Economic Theology in the Age of Enlightenment
Résumé non disponible.
Lien HAL2021
Does public debt secure social peace? A diversionary theory of public debt management
Résumé non disponible.
Lien HALFlorence Magnot-Ogilvy, Le Roman et les Echanges au XVIIIe siècle. Pertes et profits dans la fiction des Lumières
Résumé non disponible.
Lien HAL2020
Comment mettre fin à une guerre d’usure ? Quelques enseignements des modèles théoriques
Résumé non disponible.
Lien HAL2019
Faut-il détruire les ennemis de nos adversaires ? Besoin d’ennemis et réputation dans un conflit électoral
Résumé non disponible.
Lien HAL2018
The Nouvelles Ecclésiastiques (1728-1750) against their opponents : some controversies about the interest-bearing loans
Résumé non disponible.
Lien HALDeficit, monetization, and economic growth: a case for multiplicity and indeterminacy
This paper develops an original analysis of deficit monetization in a growth model with transaction costs, in which economic growth interacts with productive public expenditures. This interaction generates two positive balanced growth paths (BGP) in the long run: a high BGP and a low BGP. The transitional dynamics show that multiplicity cannot be rejected if transaction costs affect both consumption and investment expenditures, with possible indeterminacy of the high BGP. Importantly, deficit monetization is shown to reduce the parameter space producing indeterminacy.
Lien HAL
2017
Liberal Jansenists and interest-bearing loans in eighteenth-century France: a reappraisal
Résumé non disponible.
Lien HALAucune publication disponible pour le moment.
2022
Collusion and Predation Under Cournot Competition
This paper studies how predation strategies can affect the sustainability of collusion. We demonstrate that in the presence of few competitors collusion may be sustained at equilibrium for intermediate discount factors. In such instances predation implies that punishment strategies will yield low subgame perfect payoffs, thereby making collusion easier to sustain. For low discount factors collusion is not sustainable because of the high incentives to deviate to Cournot-Nash strategies. Moreover, for high discount factors it is always optimal to predate colluding firms, thus contrasting with much of the earlier literature showing that collusion is only achievable by sufficiently patient firms.
Lien HAL
2021
Do Conservative Central Bankers Weaken the Chances of Conservative Politicians?
In this paper, we challenge the claim that an independent conservative central bank strengthens the likelihood of a conservative government. In contrast, if an election is based on the comparative advantages of the candidates, an inflation-averse central banker can deter the chances of a conservative candidate because once inflation is removed, its comparative advantage in the fight against inflation disappears. We develop a theory based on a policy-mix game with electoral competition, predicting that the chances of a conservative (i.e., inflation-averse) party is reduced in the presence of tighter monetary policy. To test this prediction, we examine monthly data of British political history between 1960 and 2015. We show that a 1 percentage point increase in the interest rate in the 10 months prior to a national election decreases the popularity of a Tory government by approximately 0.75 percentage points relative to its trend.
Lien HAL
The Perils of Fiscal Rules
This paper develops a limit-cycle-based theory of debt fluctuations through a simple endogenous growth model. Public debt and deficit are introduced by relaxing the balanced-budget rule hypothesis, and assuming a simple fiscal rule. Our main result is that fiscal rules can be destabilizing, leading to (i) multiple equilibria-four balanced-growth paths can emerge-, (ii) endogenous public debt cycles, which appear both in the short and the long run, and (iii) hysteresis phenomena arising from extreme sensitivity of changes in parameters. We also reveal that a balanced-budget rule does not preclude large aggregate fluctuations. Finally, our calibration exercise highlights that our model produces asymmetric cycles consistent with observed stylized facts.
Lien HAL
2020
Réputation versus besoin d'ennemis
Pourquoi les politiciens ne résolvent-ils pas les problèmes socialement indésirables ? Une des raisons est que des politiciens peuvent être incités à ne pas résoudre les problèmes afin de conserver un avantage électoral. Cet article montre que, si la carrière des politiciens dépend des problèmes sociaux qu’ils savent résoudre avec compétence, les réformes qu’ils mettront en œuvre résulteront de l’arbitrage entre la réputation et la nécessité de garder les ennemis en vie.
Lien HAL
2019
Increasing Returns, Balanced-Budget Rules, and Aggregate Fluctuations
In a seminal contribution, Guo and Harrison (2004, JET) showed that, under a balanced-budget rule, the neoclassical growth model exhibits saddle-path stability when the adjustment is based on wasteful public spending. The present paper challenges this result in an endogenous growth framework with non-trivial dynamics of the debt-to-GDP ratio. We show that the emergence of aggregate instability dramatically depends on the strength of social labor externalities. If the labor demand is positively sloped and steeper than the labor supply, two reachable balanced-growth paths appear-a no growth trap, and a positive growth solution-that gives birth to both local and global indeterminacy, hence aggregate instability driven by self-fulfilling beliefs (sunspots). In addition, we show that a fiscal rule such that the tax rate strongly responds to public-debt increases can remove the no-growth trap, and secure positive long-run growth. JEL classification: E62; O41
Lien HAL
Budget Rules, Distortionnary Taxes, and Aggregate Instability: A reappraisal
In a seminal contribution, Schmitt-Grohé and Uribe (JPE, 1997), showed that the balanced-budget rule (BBR) produces aggregate instability in an exogenous growth model with labor tax-based adjustment. The present paper challenges this result in an endogenous growth framework with a more general budget rule, involving deficit and debt in the long-run and making the BBR a special case. We show that the emergence of aggregate instability dramatically depends on the level of public spending. In particular, low public spending ensures determinacy. However, in the case of high public spending, multiplicity arises, with four potential equilibria: two high-growth BGPs, a low-growth trap, and a "catastrophic" equilibrium where the economy asymptotically collapses. In addition, when the ratio of public spending is sufficiently large, a subcritical Hopf bifurcation appears around the low-growth trap, giving rise to a homoclinic orbit going around the neighborhood of the catastrophic equilibrium. A calibration exercise confirms that these results are obtained for realistic values of parameters.
Lien HAL
Fiscal rule and shock amplification : A stochastic endogenous growth model
This paper develops a discrete-time stochastic endogenous growth model to study the amplification role of fiscal rules. In our model, transitory shocks exert permanent effects on the level of variables in equilibrium (hysteresis), and can be strongly amplified by the public debt adjustment, leading to a procyclical amplification mechanism (the "public debt accelerator"). This procyclical stance depends on the speed of adjustment of the debt-to-GDP ratio under a fixed-fiscal rule. A cold turkey strategy removes the public debt shock, but at the risk of destabilizing other variables, while a gradualist strategy has a stabilization effect, with detrimental consequences in the long-run. Finally, we show that a flexible-fiscal rule helps smooth aggregate variables by limiting the cuts in productive public spending.
Lien HAL
Uncertainty, Overconfidence, and War
The present paper studies the causes and duration of wars by building a war of attrition game, and explores the effect of overconfidence in such settings. During the fight, each player infers his opponent's inclination in surrendering given two psychological biases jointly capturing overconfidence: illusory superiority (overestimation), and over-self-confidence (overprecision). We demonstrate that overconfidence is neither necessary, nor suffcient to have war. Yet, overconfident decision-makers are nevertheless more likely to initiate war, and to remain active longer in a conflict. Moreover, we show that the effect of overestimation on war duration may be non-monotonic, with the duration of wars increasing in overconfidence for lowly overconfident players, and decreasing for highly overconfident ones. We argue that this simple model helps understanding a host of real-world conflictive situations.
Lien HAL
Public debt versus Environmental debt: What are the relevant Tradeoffs?
The article explores the relationship between public debt and environmental debt. The latter is defined as the difference between the "virgin state" which is the maximum stock of environmental quality that can be kept intact with natural regenerations and the current quality of the environment. A theoretical model of endogenous growth is built. We show that there is a unique well-determined balanced-growth path. The public debt and the environmental debt are substitute in the short-run but complementary in the long-run. Indeed, budget deficit provides additional resources to finance pollution abatement spending, but generate also unproductive expenditures (the debt burden). This hypothesis is tested on a sample of 22 countries for the period 1990-2011. The environmental debt is measured by the cumulative CO2 emissions per capita. We use panel time-series estimators which allow for heterogeneity in the slope coefficients between countries. It appears mainly that, in the long term, an increase of 100% in public debt ratio leads to an increase of 74% in cumulative CO2 per capita. In addition, this positive long-run relationship is still present at the country and the sub-sample level, despite some differences in the short-term dynamics.
Lien HAL
Endogenous fluctuations and the balanced-budget rule: taxes versus spending-based adjustment
The present paper develops a simple theoretical setup to examine the role of the tax-spending mix of fiscal adjustments on aggregate (in)stability in indebted economies. To this end, we build an AK endogenous growth model with public debt dynamics. If the adjustment of the government's budget constraint is based on a single instrument (taxes or public spending), the economy converges towards a high-growth path. With mixed adjustment, however, another equilibrium appears (the no-growth path) that can be locally over-determine (unstable) or under-determined (stable). A hopf bifurcation can occurs at the border between the last two cases, which leads to cyclical dynamics. We also show that global indeterminacy is likely to emerge if fiscal adjustment is mainly based on public spending. A calibration of the model shows that area of indeterminacy covers reasonable values for parameters.
Lien HAL
The Relationship Between Theology and Economics: The Role of The Jansenism Movement
This article reassesses the links between the origins of the political economy and the Christian theology during the seventeenth and eighteenth centuries. I focus on the Jansenism movement-the most powerful Christian protest current in the pre-Revolution period. I reveal that the influence of this movement on economic ideas can be roughly divided into three issues. During the pre-Unigenitus (1713) period (first jansenism), (i) the original vision of labor that contrasts with the Protestant's approach and the Catholic doctrine, and (ii) the idea that self-interest can produce a social optimum were major contributions of the jansenism on economic debates. During the post-Unigenitus period (second jansenism), (iii) the confrontation between two parties-the "liberal" vs the "resistant" jansenism currents-on the interest-bearing loans issue led to the development of new economic arguments for or against the credit, while making reference to the Holy Writings.
Lien HAL
2016
Deficit Rules and Monetization in a Growth Model with Multiplicity and Indeterminacy
In response to the Great Recession, Central Banks around the world adopted " unconven-tional " monetary policies. In particular, the Fed, and more recently the ECB, launched massive debt monetization programs. In this paper, we develop a formal analysis of the short-and long-run consequences of deficit and debt monetization, through an endoge-nous growth model in which economic growth interacts with productive public expenditure. This interaction can generate two positive balanced growth paths (BGP) in the long-run: a high BGP and a low BGP, and further, depending on the form of the CIA constraint, possible multiplicity and indeterminacy. Thus, monetizing deficits is found to be remarkably powerful. First, a large dose of monetization might allow avoiding, whenever present, BGP indeterminacy. Second, monetization always allows increasing growth and welfare along the (high) BGP, by weakening the debt burden in the long-run. Third, with a CIA on consumption only, monetization provides a rationale for deficits in the long-run: for high degrees of monetization, the impact of deficits and debts on economic growth and welfare becomes positive in the steady-state.
Lien HAL
« Can a Platform Make Profit with Consumers' Mobility? A Two-Sided Monopoly Model with Random Endogenous Side-Switching »
We model a specific two-sided monopoly market in which agents can switch from a side to the other. We define two periods of time. In the first period, agents buy the platform services on each side and in the second period of time, they can possibly enhance their satisfaction by going to the other face of the platform. We analyze the link between mobility, consumer’s utility, prices and profit. We show that mobility is a valuable feature which can be compared with an increase of product quality. Finally, the firm is able to capture the mobility in its monopoly’s profit. The relative size of each group then appears as a strategical variable for the firm.
Lien HAL
Why are Reforms incomplete? Reputation versus the " need for enemies
Why do Politicians not solve social problems? One reason may be that such problems are very difficult to solve. Another one may be that Politicians have not the ability to solve difficult problems, i.e. they are “incompetent”. But there is another reason: Politicians sometimes lack the incentive to solve problems because of inefficiencies generated by electoral process in representative democracies. It is the case when Politicians have the incentive “to keep their enemies alive”, precisely because they are competent in solving the problem: once the problem removed, competent Politicians lose their electoral advantage. In this paper, we show that reputational strengths can, to some extent, circumvent Politicians’ incentives not to address the problems. If the reputation of an incumbent Politician depends on the amount of reforms he implements, and positively affects his probability of being reelected, the trade-off between reputation and the “need for enemies” leads to an incomplete set of reforms, which can handle only a part of the problems. This mechanism might contribute to the explanation of the high degree of persistence of some social or economic diseases such as, specifically, public indebtedness.
Lien HAL
2015
WHY ARE REFORMS INCOMPLETE? REPUTATION VERSUS THE " NEED FOR ENEMIES
Why do Politicians not solve social problems? One reason may be that such problems are difficult to solve, or that Politicians are incompetent. But there is another reason: in representative democracies, competent Politicians sometimes lack the incentive to solve problems to keep their enemies alive, in order to conserve an electoral advantage. This paper shows that reputational strengths can, to some extent, circumvent Politicians incentives not to address the problems. If the reputation of an incumbent Politician depends on the amount of reforms he implements, and positively affects his probability of being reelected, the trade-off between reputation and the need for enemies leads to an incomplete set of reforms, which can handle only a part of the problems. This mechanism might contribute to the explanation of the high degree of persistence of some social or economic diseases such as, specifically, public indebtedness.
Lien HAL
Is Government Debt a Vamp? Public Finance in a Transylvanian Growth Model
The vampire metaphor has been used in numerous papers describing biological interactions between two populations. Such a metaphor translates well to a standard endogenous growth model with public debt. Public debt can be assimilated to a Vamp, whose blood-sucking behavior corresponds to the harmful effect of the debt burden on productive public expenditures. However, the complete destruction of public debt in the long-run is shown to be socially undesirable, because this would imply too much distortionary taxation, with damaging effects on the balanced growth path. By identifying ecological or biological processes with usual national account relationships, this analysis is one step further in the integration of macroeconomics and environmental economics.
Lien HAL
Deficit Rules and Monetization in a Growth Model with Multiplicity and Indeterminacy
In response to the Great Recession, Central Banks around the world adopted " unconven-tional " monetary policies. In particular, the Fed, and more recently the ECB, launched massive debt monetization programs. In this paper, we develop a formal analysis of the short-and long-run consequences of deficit and debt monetization, through an endoge-nous growth model in which economic growth interacts with productive public expenditure. This interaction can generate two positive balanced growth paths (BGP) in the long-run: a high BGP and a low BGP, and further, depending on the form of the CIA constraint, possible multiplicity and indeterminacy. Thus, monetizing deficits is found to be remarkably powerful. First, a large dose of monetization might allow avoiding, whenever present, BGP indeterminacy. Second, monetization always allows increasing growth and welfare along the (high) BGP, by weakening the debt burden in the long-run. Third, with a CIA on consumption only, monetization provides a rationale for deficits in the long-run: for high degrees of monetization, the impact of deficits and debts on economic growth and welfare becomes positive in the steady-state.
Lien HAL
Can a Platform Make Profit with Consumer' Mobility? A Two-Sided Monopoly Model with Random Endogenous Side-Swiching
We model a specific two-sided monopoly market in which agents can switch from a side to the other. We define two periods of time. In the first period, agents buy the platform services on each side and in the second period of time, they can possibly enhance their satisfaction by going to the other face of the platform. We analyze the link between mobility, consumer’s utility, prices and profit. We show that mobility is a valuable feature which can be compared with an increase of product quality. Finally, the firm is able to capture the mobility in its monopoly’s profit. The relative size of each group then appears as a strategical variable for the firm.
Lien HAL
2014
La vision du travail chez les premiers jansénistes : Entre spiritualité et politique au coeur du grand siècle
L'influence, en France, du Jansénisme, sur les premiers développements de l'économie politique, notamment autour du Cercle de Gournay, est aujourd'hui quelque chose de bien renseigné. A leur tour, ces développements de l' économie politique pré-classique vont nourrir la volonté d’émancipation de la Bourgeoisie de Robe au XVIIIe siècle. Notre hypothèse de départ est que le Jansénisme a pu ainsi jouer, dans le grand pays Catholique qu'est alors la France, le rôle, identifié depuis Max Weber, qu'a jouée,dans les pays où elle domine, la diffusion de « l'éthique protestante » sur le développement d'un « esprit du capitalisme ». Nous revendiquons alors la nécessité de revenir au sources théologiques du « premier jansénisme », dans sa volonté de mener une Contre-Réforme qui puise à la double source de l'église tridentine et de l'augustinisme, pour comprendre comment « l'éthique » janséniste a pu justifier des conduites de vie relevant d'une forme « d'esprit du capitalisme ». Pour identifier cette singularité de la théologie janséniste, et l'influence qu'elle a pu avoir sur les conduites de vie et les postures politiques de la bourgeoisie libérale au XVIIIe siècle, nous centrons cet article sur la vision qui peut en découler du travail comme acte libre et hédoniste.
Lien HAL
2020
Public debt versus Environmental debt: What are the relevant Tradeoffs?
Résumé non disponible.
Lien HAL2019
Public debt versus Environmental debt: What are the relevant Tradeoffs?
Résumé non disponible.
Lien HALPublic debt versus Environmental debt: What are the relevant Tradeoffs?
Résumé non disponible.
Lien HALEndogenous fluctuations and the balanced - budget rule: taxes versus spending - based adjustment
Résumé non disponible.
Lien HALIncreasing Returns, Balanced-Budget Rules, and Aggregate Fluctuations
Résumé non disponible.
Lien HALThe Relationship Between Theology and Economics: The Role of The Jansenism Movement
Résumé non disponible.
Lien HALEndogenous fluctuations and the balanced-budget rule: taxes versus spending-based adjustment
Résumé non disponible.
Lien HALEndogenous fluctuations and the balanced-budget rule: taxes versus spending-based adjustment
Résumé non disponible.
Lien HALEndogenous fluctuations and the balanced-budget rule: taxes versus spending-based adjustment
Résumé non disponible.
Lien HAL