Publications

La plupart des informations présentées ci-dessous ont été récupérées via RePEc avec l'aimable autorisation de Christian Zimmermann
Conditions necessary for the sustainability of an emerging area: The importance of banking and financial regional criteriaJournal articleCéline Gimet, Journal of Multinational Financial Management, Volume 17, Issue 4, pp. 317-335, Forthcoming

The last financial crises have revealed the vulnerability of many emerging countries. Yet, within an economically integrated area, some groups of countries have been spared the disastrous consequences of these crises. The purpose of this article is to underline the similarities between these countries in order to draw up a set of regional criteria that would protect an area against speculative attacks. Using a probit analysis, we show that the convergence of some banking and financial indicators towards reference levels guarantees the confidence of international lenders, which in turn limits financial contagion. A narrow margin between the amount of external debt, in particular the short-term debt of the country and a reference level constitutes a protection against the risk of illiquidity. Similarly, a low domestic credit in comparison with the international reserves of the economy is also an indicator of the sustainability of an area for international lenders that ensures its stock exchange stability.

The impacts of standard monetary and budgetary policies on liquidity and financial markets: International evidence from the credit freeze crisisJournal articleMarie-Hélène Gagnon et Céline Gimet, Journal of Banking & Finance, Volume 37, Issue 11, pp. 4599-4614, Forthcoming

This paper evaluates the domestic and international impacts of lowering short-term interest rates and increasing budget spending on several indicators of liquidity, volatility, credit and economic activity. Data from the 2003–2011 period in the United States, the Euro zone and Canada were used to develop two SVAR models for assessing the national effectiveness and the international spillovers of monetary and budgetary policies during the credit freeze crisis. While monetary policies caused a temporary decrease in volatility and increase in liquidity in North American stock markets, the shocks were mainly domestic and ineffective at generating liquidity in the banking sector. In contrast, government spending shocks had a positive impact on credit and consumption, especially in Europe and Canada. Moreover, budgetary policies also had a positive international spillover effect on consumption and credit, especially for smaller economies such as Canada.

Variational analysis and Variational rationality in Behavioral sciences: stationary trapsJournal articleBoris S. Mordukhovich et Antoine Soubeyran, Optimization, Forthcoming

This paper concerns applications of variational analysis to some local aspects of behavioral science modeling by developing an effective variational rationality approach to these and related issues. Our main attention is paid to local stationary traps, which reflect such local equilibrium and the like positions in behavioral science models that are not worthwhile to quit. We establish constructive linear optimistic evaluations of local stationary traps by using generalized differential tools of variational analysis that involve subgradients and normals for nonsmooth and nonconvex objects as well as variational and extremal principles.

Pollution and growth: The role of pension in the efficiency of health and environmental policiesJournal articleArmel Ngami et Thomas Seegmuller, International Journal of Economic Theory, Forthcoming

This paper analyzes the effect of a pay-as-you-go pension system on the evolution of capital and pollution, and on the efficiency of an environmental versus health policy. In an overlapping generations model, we introduce endogenous longevity that depends on pollution and health expenditures. Global dynamics may display multiple balanced growth paths (BGPs). We show that by discouraging savings, a policy that promotes the pension system enlarges the environmental poverty trap. More surprisingly, the environmental policy has contrasting effects according to the significance of the pension system. If it has a small size, a more environmentally-friendly policy enlarges the environmental poverty trap and leads to a rise in capital over pollution at the highest stationary equilibrium. In contrast, in economies where intergenerational solidarity is well developed, capital over pollution decreases at the highest BGP. In such a case, the environmental policy does not necessarily lead to a better longevity and growth.

An evolutionary finance model with short selling and endogenous asset supplyJournal articleRabah Amir, Sergei Belkov, Igor V. Evstigneev et Thorsten Hens, Economic Theory, Forthcoming

Evolutionary finance focuses on questions of “survival and extinction” of investment strategies (portfolio rules) in the market selection process. It analyzes stochastic dynamics of financial markets in which asset prices are determined endogenously by a short-run equilibrium between supply and demand. Equilibrium is formed in each time period in the course of interaction of portfolio rules of competing market participants. A comprehensive theory of evolutionary dynamics of this kind has been developed for models in which short selling is not allowed and asset supply is exogenous. The present paper extends the theory to a class of models with short selling and endogenous asset supply.

Control theory in infinite dimension for the optimal location of economic activity: The role of social welfare functionJournal articleRaouf Boucekkine, Giorgio Fabbri, Salvatore Federico et Fausto Gozzi, Pure and Applied Functional Analysis, Forthcoming

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.

Modeling the impact of product quality on dynamic pricing and advertising policiesJournal articleRégis Y. Chenavaz, Gustav Feichtinger, Richard F. Hartl et Peter M. Kort, European Journal of Operational Research, Forthcoming

The marketing-mix of price–quality and advertising–quality relationship is well studied. Less understood is the price–advertising–quality relationship. This article fills the gap, investigating the interplay between price, advertising, and quality in an optimal control model. Our results generalize the condition of Dorfman–Steiner in a dynamic context. Also, they point to the impact of greater product quality on the dynamic policies of pricing and advertising. Furthermore, a phase diagram analysis shows that quality develops monotonically in time and converges to a unique steady state. We also show that quality investment could either decrease or increase over time but this depends on its effectiveness. Our results spot the profitable opportunities of a firm managing a more complex marketing-mix.

The Welfare Consequences of Centralization: Evidence from a Quasi-Natural Experiment in SwitzerlandJournal articleSarah Flèche, Review of Economics and Statistics, Forthcoming

Many countries are reallocating tasks and powers to more central levels of government. To identify centralization’s welfare effects, I use a difference-in-differences design that relies on time and cross-cantonal variation in the implementation of centralization reforms in Switzerland. I find that centralization provokes significant decreases in residents’ life satisfaction. I identify one mechanism driving the effect, namely the procedural disutility that individuals experience from having less influence over the formulation of political decisions. This effect is largest among individuals with higher expected benefits from being involved in the political decision process, with detrimental effects on local political participation.

On Zipf's law and the bias of Zipf regressionsJournal articleChristian Schluter, Empirical Economics, Forthcoming

City size distributions are not strictly Pareto, but upper tails are rather Pareto like (i.e. tails are regularly varying). We examine the properties of the tail exponent estimator obtained from ordinary least squares (OLS) rank size regressions (Zipf regressions for short), the most popular empirical strategy among urban economists. The estimator is then biased towards Zipf's law in the leading class of distributions. The Pareto quantile-quantile plot is shown to offer a simple diagnostic device to detect such distortions and should be used in conjunction with the regression residuals to select the anchor point of the OLS regression in a data-dependent manner. Applying these updated methods to some well-known data sets for the largest cities, Zipf's law is now rejected in several cases.

The impact of ICTs and digitalization on productivity and labor share: evidence from French firmsJournal articleGilbert Cette, Sandra Nevoux et Loriane Py, Economics of Innovation and New Technology, pp. 1-24, Forthcoming

Taking advantage of an original firm-level survey carried out by the Banque de France, we empirically investigate how the employment of ICT specialists (in-house and external) and the use of digital technologies (cloud and big data) have an impact on firm productivity and labor share. Our analysis relies on the survey responses in 2018 of 1,065 French firms belonging to the manufacturing sector and with at least 20 employees. To tackle potential endogeneity issues, we adopt an instrumental variable approach as proposed by Bartik (1991, Who Benefits from State and Local Economic Development Policies? Kalamazoo, MI: W.E. Upjohn Institute for Employment Research.). The results of our cross-section estimations point to a large effect: ceteris paribus, the employment of ICT specialists and the use of digital technologies improve a firm’s labor productivity by about 23% and its total factor productivity by about 17%. Conversely, the employment of in-house ICT specialists and the use of big data both have a detrimental impact on labor share, of about 2.5 percentage points respectively.