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Accueil > Séminaires réguliers > Séminaires Caen > Archives

2012-2013

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Les séminaires du CREM à Caen ont lieu salle EG107
de l’UFR Sciences Economiques et de Gestion de Caen, 19 rue Claude Bloch,
le lundi à partir de 14h

 

 

 


  • mardi 25 juin 2013 , 14h15 à 15h45

Intervenant Annick Laruelle - University of the Basque Country (UPV/EHU)
Invité par / invited by Vincent Merlin
Thème / Subject Régle de vote
Titre / title To approve or not to approve : this is not the only question.
Co-auteurs/Joint work with José Carlos Alcantud
Résumé / abstract This paper deals with electing candidates. In elections voters are frequently offered a small set of actions (voting in favor of one candidate, voting blank, spoling the ballot, and not showing up). Thus voters can express neither a negative opinion nor an opinion on more than one candidate. Approval voting partially fills this gap by asking an opinion on all the candidates. Stll, the choice is only between approval and non approval. However non approval may mean disapproval or just indifference or even absence of sufficient knowledge for approving candidate. In this paper we characterize this dis&approval voting rule, a natural extensionof approval voting that distinguishes between indifference and disapproval.
Lien / download https://addi.ehu.es/bitstream/10810/9052/1/IL6312.pdf
  • lundi 17 juin 2013 , 14h15 à 15h45

Intervenant Tritah Ahmed - Université du Maine, GAINS
Invité par / invited by Jean Bonnet
Thème / Subject Occupational mobility
Titre / title Social Mobility and Educational Financing in General Equilibrium
Résumé / abstract This paper studies the joint determination of inequality and social mobility under a public and a private education financing regime. For this purpose we develop an Overlapping Generation Model where heterogeneous individuals make occupational choices. Agents differ with respect to their talent and families backgrounds. Students form their believes over their talent at school by observing the social mobility trajectories of their parents. The endogeneous distribution of believes determines the occupational mobility which in turn influences the distribution of human capital across occupations, their relative returns and in-fine the occupational incentives. I show that social mobility is driven by the skill premium offered to uneducated background children. A main implication of the model is that a publicly financed education provides better opportunities for children from disadvantaged background to climb the social ladder only if inherited factors of production such as parental human capital and school quality are the main determinants for the accumulation of human capital. Instead, if learning effort at school is the main determinant of human capital accumulation, a private system may generate higher occupational mobility despite higher inequality. The later result is due to the fact that in this financing regime agents make a better use of their accumulated believes and can appropriate the full returns of their learning effort.
  • lundi 10 juin 2013 , 14h15 à 15h45

Intervenant Siani Tchoumaetieu Joseph - Université de Normandie, UCBN
Invité par / invited by Séminaire interne
Thème / Subject Multidimensional poverty, Capability Approach
Titre / title Multidimensional Poverty Analysis in Cameroon : Estimates and Policy Implications
Résumé / abstract In economics, the dominant view is to conceptualize poverty as lack of income and measure it empirically by unidimensional indicators such as income or consumption expenditures. However, since Sen’s capability approach, many authors insist on the necessity of extending the definition of poverty to aspects of well-being not captured by income measures. To measure poverty in this way, Alkire and Foster (2007) propose a multidimensional poverty measure consisting of an identification method ρ_k that extends the traditional intersection and union approaches, and a class of poverty measures M_α. The identification step employs two forms of cutoff : one within each dimension to determine whether a person is deprived in that dimension, and a second across dimensions that identifies the poor by ‘counting’ the dimensions in which a person is deprived. The aggregation step employs the FGT measures that reflect the breadth, depth and severity of multidimensional poverty. This method is applied to estimate multidimensional poverty in Cameroon. Nine dimensions are considered for estimations (education, housing, sanitation, water, cooking, electricity, consultation, people per room and income). The results show important differences in poverty among regions. Comparing findings with income-based measures show that considering additional dimensions leads to different region rankings. In addition, poverty is decomposed by rural and urban location, by region and by dimension. Rural areas are identified as the poorest, although urban areas present high levels of deprivation in sanitation and water. Furthermore, sanitation is identified as giving the highest contribution to overall multidimensional poverty. Finally, some robustness and flexibility analyses are performed.
  • lundi 3 juin 2013 , 14h15 à 15h45

Intervenant David Ettinger - Université Paris Dauphine (PLS)
Invité par / invited by Sara Biancini
Thème / Subject Enchères informations
Titre / title Hinding information in open auctions with jump bids
Co-auteurs/Joint work with Fabio Michelucci
Résumé / abstract We analyze a rationale for hiding information in open auction formats. We focus on the incentives for a bidder to call a price higher than the highest standing one in order to prevent the remaining active bidders from aggregating more accurate information that could be gathered by observing the exact drop out values of exiting bidders. Necessary conditions for the existence of jump bids with such motivations are provided. Finally, we show that there is no clear-cut effect of jump bids on efficiency and expoected revenue and introduce several specific results.
Lien / download 2013-06-03_Ettinger.pdf
  • lundi 27 mai 2013 , 14h15 à 15h45

Intervenant Bram, W.I., Driesen - University of Heidelberg
Invité par / invited by Boniface Mbih
Thème / Subject Game Theory, Bargaining
Titre / title Implementations of asymmetric bargaining solutions
Co-auteurs/Joint work with Nora Wegner and Peter Eccles
Résumé / abstract This paper provides a non-cooperative foundation for asymmetric versions of the continuous Raiffa solution and the Nash bargaining solution. Specifically, we consider a continuous-time bargaining model with a finite horizon, where each players opportunity to make proposals is determined by an independent Poisson process. Under the assumption that future payoffs are not discounted, the payoffs realized approach the continuous Raiffa solution as the time horizon goes to infinity. On the other hand, if future payoffs are discounted, then equilibrium payoffs approach the Nash bargaining solution. In both cases the weights reflecting the asymmetries among the players are given by the arrival rates of the Poisson processes.
  • lundi 13 mai 2013 , 14h15 à 15h45

Intervenant Jérôme Renault - GREMAQ, TSE et département de Maths, Université Toulouse 1
Invité par / invited by Vincent Merlin, Maurice Salles
Thème / Subject
Titre / title Dynamic Sender-Receiver Games
Co-auteurs/Joint work with Eilon Solan and Nicolas Vieille
Résumé / abstract We consider a dynamic version of sender-receiver games, where the sequence of states follows an irreducible Markov chain observed by the sender. Under mild assumptions, we provide a simple characterization of the limit set of equilibrium payoffs, as players become very patient. Under these assumptions, the limit set depends on the Markov chain only through its invariant measure. The (limit) equilibrium payoffs are the feasible payoffs that satisfy an individual rationality condition for the receiver, and an incentive compatibility condition for the sender.
Lien / download Dynamic Sender-Receiver Games

GIF

  • lundi 6 mai 2013 , 14h15 à 15h45

Intervenant Pascale Petit - Université d’Evry, EPEE
Invité par / invited by Mathieu Bunel
Thème / Subject Discrimination à l’embauche liée à l’origine et remédiation
Titre / title Etre Meilleur Apprenti de France : Quels effets sur l’accès à l’emploi ?
Co-auteurs/Joint work with Florent Frémigacci, Loïc Parquet, Guillaume Pierné
Résumé / abstract Cette étude examine si la mention d’une récompense à un coucours d’excellence professionnelle (meilleurs apprentis de France, « MAF ») dans le curriculum vitae a un effet sur la discrimination à l’embauche liée à l’origine. L’évaluation est réalisée sur des données expérimentales construites à l’aide de deux campagnes de testing conduites sur des professions du Bâtiment entre avril et septembre 2011 dans la région Ile de France. Nous trouvons trois résultats principaux. Tout d’abord, dans les professions testées, la mention d’une distinction au concours MAF augmente toutes choses égales par ailleurs les chances d’obtenir un entretien d’embauche. Ensuite, le supplément de chances d’accéder à un entretien induit par une récompense au concours MAF bénéficie également aux candidats issus de l’immigration. Ainsi, révéler ses qualités professionnelles par la mention d’une distinction au concours MAF permet à un jeune issu de l’immigration d’avoir autant de chances qu’un jeune d’origine française titulaire du même diplôme mais ne faisant mention d’aucune récompense. Dans ce cas, le jeune issu de l’immigration tend même à avoir un peu plus de chances que son concurrent d’origine française. Ayant une information qu’ils considèrent fiable sur les qualités professionnelles des candidats, les recruteurs sont plus enclins à recruter des jeunes issus de l’immigration. A ce titre, cette étude montre que ce type de concours d’excellence constitue un levier qui permet de réduire la composante « statistique » de la discrimination liée à l’origine. Plus généralement, les signaux d’excellence professionnelle constituent un moyen de réduire la composante statistique de la discrimination à l’embauche, pourvu que les informations sur la qualité du candidat révélées par une récompense soient considérées comme fiables par l’employeur. Pour autant, ce levier n’est pas suffisant pour éliminer la discrimination. On constate en effet la persistance d’une discrimination à l’embauche liée à l’origine significative parmi les candidats distingués au concours MAF. Celle-ci peut en particulier être induite par l’existence de préférences discriminatoires des employeurs, des autres salariés de l’entreprise ou encore de la clientèle. Cette étude montre donc qu’il existe empiriquement deux sources de discrimination qui se cumulent, l’une liée aux préférences discriminatoires, l’autre liée à l’imperfection de l’information lors du processus de recrutement.

GIF

  • lundi 15 avril 2013 , 14h15 à 15h45

Intervenant Nabil Khelil - Normandie Université, Unicaen, CREM CNRS UMR6211
Invité par / invited by Séminaire interne
Thème / Subject Entrepreneurship & Strategic Management
Titre / title What are we talking about when we talk about entrepreneurial failure ?
Résumé / abstract The significant differences between successful and failed entrepreneurs provide compelling arguments to study the later separately. Nevertheless, despite high failure rate of new ventures, little researchers have focused specifically on failed entrepreneurs. In addition, entrepreneurial failure is a complex and multiform phenomenon that cannot be reduced to a linear discriminant model, which widely used to identify the differences between success and failure in new venture creation. The contribution of this study is to provide a better understanding of entrepreneurial failure. Precisely, this research aims to highlight the multiple forms of this phenomenon. To this end, we develop an empirically grounded taxonomy using quantitative data generated from questionnaire responses from 105 failed entrepreneurs. The taxonomy describes five different types of failed entrepreneurs labelled “lost”, the “supported at arm’s length”, the “megalomaniac”, the “dissatisfied with lord” and “big-time gambler”. The entrepreneurial failure taxonomy developed in this research, can be used by professionals like counsellors or consultants, as a situation-based framework to help currently failing entrepreneurs as well as prospective entrepreneurs.

GIF

  • lundi 8 avril 2013 , 14h15 à 15h45

Intervenant Béatrice Cherrier - Normandie Université, Unicaen, CREM CNRS UMR6211
Invité par / invited by Séminaire interne
Thème / Subject Histoire de la pensée économique
Titre / title The fragmentation of “collective decision” in the postwar era : from welfare economics and public finance to social choice, public choice and public economics.
Co-auteurs/Joint work with Jean-Baptiste Fleury - THEMA, Université de Cergy-Pontoise
Résumé / abstract The purpose of this paper is to explain why seemingly common research themes such as voting procedures, tax design, or the welfare analysis of policies are nowadays approached within separate academic journals, courses or conferences. Our thesis is that the way these themes were conceived before World War II by welfare economists and public finance specialists underwent some radical transformations in the forties, with communities, methods of inquiries and fields being redesigned around the core question of collective action in the following decades. The forties wars (hot and cold) placed new and contradictory requirements on economists’ practices and theoretical schemes. On the one hand, the daily business of organizing the production of public and private goods, of levying taxes and borrowing, of allocating the workforce to industries, of preventing inflation, e.g., the application of theories, required the definition and implementation of evaluation and choice criteria. At the same time, the growing internal pressures — usually traced to Lionel Robbins’ 1932 redefinition of the scope and methods of economics – to strip economic analysis of ethical and psychological content, and the external suspicion Mccarthyites showed toward planning and Keynesian ideas commanded the pursuit of “value-free” analysis. A possible way to preserve their objectivity, economists sensed, was to ground economic analysis solely on agents’ values, preferences and choices, but whether it was possible and legitimate to combine them into a collective criterion was still unclear. As Richard Musgrave, James Buchanan and Paul Samuelson, among many others, were struggling to reshape the theoretical foundations of market organization and state intervention, Arrow proposed in 1951 a formal and philosophical framework for the study of social choices that drew on the recent advances in individual choice theory. Such achievement provided a reference point for all those economists who turned to the study of collective decisions within countries, the state, governmental agencies, groups, parties or firms in the following decades. Some scholars focused on its abstract modeling and, under the leadership of Amartya Sen, reclaimed an expertise on normative judgments, in particular justice. Others, including Buchanan and Gordon Tullock, Anthony Downs and Mancur Olson, sought to analyze and compare the various institutions in which collective decisions took place. Yet another more loosely organized group became involved in the study of the numerous theoretical and practical cases when markets fail and state intervention is required (public goods, externalities, tax or debt funding, etc.). In the late sixties, in the context of an increasing demand for institutionalization, these three strands – formal, institutional, applied – became entrenched in separate fields : social choice, public choice and public economics respectively.

GIF

  • lundi 25 mars 2013 , 14h15 à 15h45

Intervenant Laurent Gourvès - LAMSADE, Université Paris Dauphine (CNRS-PLS)
Invité par / invited by Vincent Merlin et Angelo Fanelli
Thème / Subject Algorithmic Game Theory
Titre / title Worst case guarantee for the least happy agent in a matroid
Co-auteurs/Joint work with Jérôme Monnot - LAMSADE, Université Paris Dauphine (CNRS-PLS)
Co-auteurs/Joint work with Lydia Tlilane - LAMSADE, Université Paris Dauphine (CNRS-PLS)
Résumé / abstract "We consider the problem of choosing a common solution to two agents. To be fair, one can try to find a solution that maximizes the utility of the least happy agent. A related question is to find the largest real r between 0 and 1, such that a solution S is guaranteed to exist, and each agent’s valuation for S is r times his maximum valuation for a feasible solution. This problem has already been studied by Demko and Hill in the context of sharing indivisible goods. They proposed a partial characterisation of r for any number n of agents. The analysis is based on a parameter alpha defined as the maximum valuation that an agent has for a single item. Demko and Hill proposed a lower bound on r which decreases with alpha.
We propose to study a problem which generalizes the allocation of indivisible goods. It is about finding a common base in a matroid. We follow the approach of Demko and Hill, and give a similar (and even strenghtened) lower bound on r. The result is obtained via a simple greedy algorithm which takes as input the valuations of the agents for the elements of the matroid.
Finally, we propose an extension of the well known divide-and-chosse procedure for matroids."

GIF

  • lundi 4 mars 2013 , 14h15 à 15h45

Intervenant Régis Renault, - Université de Cergy Pontoise, THEMA
Invité par / invited by Jean Bonnet, Nicolas Le Pape
Thème / Subject Economie industrielle
Titre / title Platform Contents
Résumé / abstract A monopoly platform hosts some advertisers who compete with each other on a market for horizontally differentiated products. Products sold may be of two types. Either they are mass market products that appeal broadly to the entire consumer population or they are niche products that are tailored to the tastes of some particular group. If ads are the only content provided by the platform, then it trades off the attractiveness of the content for users with the profitability of the market for advertisers that in turn determine the level of ad prices that the platform can charge. The consumers’ surplus from joining the platform is larger if there is a larger proportion of niche products that advertise. From their point of view, an increase in the proportion of mass market products is equivalent to an increase in the cost of searching through the ads. This in turn makes the market more profitable for advertisers of both types. The platform chooses between two business models. If search costs are low, and the potential proportion of mass market product advertisers is in some intermediate range, it lets in both types of advertisers. Otherwise, only niche market products are advertised on the platform. Mass market product ads include a price but no product information. Niche product ads typically include partial product information but no price. Advertisers selling mass market products are more likely to resort to persuasive advertising. If non advertising content is not too costly to provide, then the platform may find it profitable to have only mass market product ads along with some additional content that attracts consumers. In a duopoly model with ordered search, the platform prefers to have consumers first looking at the mass market product ads and then at the niche product ads.

GIF

  • lundi 11 février 2013 , 14h15 à 15h45

Intervenant Jean-François Maguet - Normandie Université, Unicaen, CREM CNRS UMR6211
Invité par / invited by Séminaire interne
Thème / Subject Welfare Economics, Equality of Opportunity, Mechanism Design.
Titre / title An Egalitarian Mechanism on Primary Opportunity of No-Life Regret
Résumé / abstract "Starting from the egalitarian rules of distribution proposed by John Roemer (1999) and Dirk Van de Gaer (2003), we provide another approach of the traditional problem of equality of opportunity.
Notably identifying a life through the set of all (multidimensional) individually consented ambitions, we analyze a worrying case : any agent may regret his own life with regard to a constraining context and/or to the situation of any other one. From this, we examine the situation in which any agent may not have enough advantages for reaching a level of welfare that he thinks it is ‘contextually sufficient’ ; advantages may be unequally distributed. Faced with such a point, we are concentrated on the problem of equality of opportunity of no life regret (and implicitly, on the way to improve agents’ welfare relatively to their respective ambitions). In this perspective, we develop an egalitarian mechanism.
Considering the constraining context associated to the society in which agents live, the proposed mechanism is foremost based on the contextual-equivalence principle that concerns any individual primary ambition (a primary ambition being an alternative that is individually consented in disregard of any context) : any agent should achieve an ambition - over a given context - that procures to him a level of welfare equivalent to the one associated to a situation in which s/he would rather pursue his primary ambition - over a less contraining context.
"

GIF

  • lundi 4 février 2013 , 14h15 à 15h45

Intervenant Claire Chambolle - INRA (Ivry)
Invité par / invited by Clémence Christin
Thème / Subject "Retailing, Buyer power, Vertical Restraints, Competition Policy, Innovation
Industrial Organization"
Titre / title The impact of retail mergers on food prices : evidence from France
Co-auteurs/Joint work with Allain, Marie-Laure - CREST
Co-auteurs/Joint work with Stéphane Turolla - INRA UMR SMART
Co-auteurs/Joint work with Sofia Villas-Boas - University of California, Berkeley
Résumé / abstract "Using consumer panel data, we analyse the impact of a merger in the retail sector on food prices in France.
In order to capture the local dimension of retail competition, we define local markets as catchment areas around each store. We develop a difference-in-differences analysis to compare price changes in local markets where the merger did modify the ownership structure (treated group) to price changes in local markets where the merger did not affect the ownership structure (control group). We find that the merger had no significant effect on the prices of the merging firms, but significantly raised the competitors’ prices. We interpret these results as the combination of efficiency gains for the merging firms and possible coordinated effects or a decrease in differentiation.
"

GIF

  • lundi 28 janvier 2013 , 14h15 à 15h45

Intervenant Arnold Vialfont - ERUDITE, Université Paris-Est, Créteil
Invité par / invited by Nicolas Le Pape
Thème / Subject Economie Industrielle, Droit de la Concurrence
Titre / title Commitments in Antitrust
Co-auteurs/Joint work with Philippe Choné - CREST
Co-auteurs/Joint work with Saïd Souam - EconomiX
Résumé / abstract Competition agencies have the power to close an antitrust case in return for the firm’s commitment to end the alleged infringement. We examine how such a procedure affects deterrence and consumer welfare. We first show that commitments are not proposed by firms who benefit much from the practice, but are always proposed in cases where the firm could be deterred with the usual trial sanction : this procedure necessarily lowers the deterrent effect of the competition authorities’ intervention. Under asymmetric information, commitments may enhance consumer surplus : they allow for shortened proceedings and avoid trial type-II errors. However, considering type-I errors this procédure may be inefficient. We find that the correlation between the firm’s gain from the practice and consumer harm determines the optimal usage frequency of the commitments procedure : monotonic correlations push to pure strategies from the competition authority, while a stochastic use may be optimal otherwise. We finally show that trial’s expected sanctions and commitments may be strategic complements : the commitments procedure is not always an alternative to a lack of efficiency of the competition authority’s intervention.

GIF

  • lundi 21 janvier 2013 , 14h15 à 15h45

Intervenant Jean-Sébastien Gharbi - Sciences Po Grenoble
Invité par / invited by Muriel Gilardone
Thème / Subject Economie Normative et Justice Sociale
Titre / title Sur le sens du non welfarisme dans le modèle ELIE de redistribution des revenus de Kolm
Co-auteurs/Joint work with Yves Meinard
Résumé / abstract "L’économie du bien-être ou welfarisme, qui pose que les seules informations pertinentes pour juger les états sociaux sont les utilités individuelles (Sen, 1979), a très longtemps occupé une place hégémonique dans le champ de l’économie normative. Le modèle ELIE de redistribution des revenus (ELIE signifiant Equal-Labour Income Equalization) se présente, de manière à la fois très explicite et récurrente, comme rompant avec cette tradition aujourd’hui encore dominante (Kolm, 2005, 2011b).
Ce papier interroge le sens de cette prise de distance avec le welfarisme. Après avoir procédé à un certain nombre de mises au point concernant, d’une part, le modèle ELIE et, d’autre part, le welfarisme, nous discutons les différents aspects de la rupture du modèle ELIE de redistribution des revenus avec le welfarisme."

GIF

  • lundi 14 janvier 2013 , 14h15 à 15h45

Intervenant Eric Kamwa - Université Caen Basse-Normandie
Invité par / invited by Séminaire interne
Thème / Subject Election des comités, critère majoritaire, extension des préférences
Titre / title Coincidence of Condorcet Committees
Co-auteurs/Joint work with Vincent Merlin - Université Caen Basse-Normandie
Résumé / abstract The Condorcet Committee à la Gehrlein (CCG) is a fixed-size subset of candidates such that none of its member is beaten in pairwise majority by any candidate outside. The Condorcet Committee à la Fishburn (CCF) is a fixed size subset of candidates that is preferred to all other subsets of the same size by a majority of voters. In general, these two types of Condorcet committees do not always exist. Using lexicographic extension of preferences, we define some conditions for which these committees coincide when they exist. We show that when there are simultaneously a CCG and a CCF by lexicographic extension of preferences, they always coincide. Unfortunately, with more than three candidates, a CCG may exist while it is not the case for the CCF. In four-candidate elections, we compute the conditional probabilities of these events under the Impartial Culture assumption : in 21.4% of the cases, the CCG fails to meet the CCF.

GIF

  • lundi 17 décembre 2012 , 14h15 à 15h45

Intervenant Olivier Bos - Université Paris 2
Invité par / invited by Daniel Danau
Thème / Subject Economie Publique, Microéconomie Théorique
Titre / title Auctions with Prestige Motives
Co-auteurs/Joint work with Tom Truyts - CEREC, University St Louis
Résumé / abstract We present a model of auctions in which all bidders care about the others’ perception of their valuation. That could happen in a lot of auctions such as charity auctions and auctions for art. Bidding behavior is altered as prestige motives provide new incentives to losers and winner. We study first and second-price auctions and English auctions. Revenue equivalence is lost whenever a bidder benefits from a prestige motive and a new revenue ranking is determined.

GIF

  • lundi 10 décembre 2012 , 14h15 à 15h45

Intervenant Nicolas Maudet - Université Paris 6
Invité par / invited by Vincent Merlin
Thème / Subject Computational Social Choice
Titre / title Communication and compilation issues in (computational) social choice
Résumé / abstract "Computational social choice finds its roots in the seminal results of Bartholdi, Tovey and Trick who investigated the algorithmic complexity of deciding the winner for a number of voting rules. Another fruitful —perhaps less known— trend of research at the interface of computer science and social choice deals with communication issues.
In this talk I shall first give an overview of communication issues in social choice, from a computational perspective. I will then focus on the compilation complexity problem, which can be seen as one-round communication complexity : suppose a subset of voters have casted their ballots, while some others are missing. What is the minimal amount of information required to encode this partial profile so that the winner can still be decided when the profile is completed ?
"

GIF

  • lundi 10 décembre 2012 , 14h15 à 15h45

Intervenant Nicolas Maudet - Université Paris 6
Invité par / invited by Vincent Merlin
Thème / Subject Computational Social Choice
Titre / title Communication and compilation issues in (computational) social choice
Résumé / abstract "Computational social choice finds its roots in the seminal results of Bartholdi, Tovey and Trick who investigated the algorithmic complexity of deciding the winner for a number of voting rules. Another fruitful —perhaps less known— trend of research at the interface of computer science and social choice deals with communication issues.
In this talk I shall first give an overview of communication issues in social choice, from a computational perspective. I will then focus on the compilation complexity problem, which can be seen as one-round communication complexity : suppose a subset of voters have casted their ballots, while some others are missing. What is the minimal amount of information required to encode this partial profile so that the winner can still be decided when the profile is completed ?
"

GIF

  • lundi 3 décembre 2012 , 14h15 à 15h45

Intervenant Danielle Zwarthoed - Université Paris-Est
Invité par / invited by Muriel Gilardone
Thème / Subject Philosophie économique, capabilités, théorie du choix social
Titre / title Capabilités et choix social dans les travaux d’Amartya Sen : vers un accord raisonné
Résumé / abstract L’apport d’Amartya Sen à l’économie du bien-être et à la philosophie politique normative est double, comprenant à la fois ses travaux en théorie du choix social et l’élaboration des capabilités comme espace d’évaluation, distinct de l’espace des ressources comme de celui des utilités. Mais A. Sen a toujours refusé de définir une « liste » de capabilités fondamentales à l’aide d’un critère objectif, ou encore d’intégrer celles-ci à une théorie de la justice : seul un « accord raisonné » (reasoned agreement) entre les membres de la société serait susceptible d’offrir une évaluation objective des capabilités. Cet « accord raisonné » est présenté à l’aide du vocabulaire de la théorie du choix social : se pourrait-il alors qu’il existe ici un point de jonction entre les deux versants des travaux de Sen ? Cela ne doit pas occulter l’hétérogénéité des deux approches, hétérogénéité à la fois stylistique et conceptuelle : stylistique, dans la mesure où la théorie du choix social se distingue par son formalisme, ce qui est rarement le cas des travaux sur les capabilités ; conceptuelle, du fait du caractère originellement welfariste de la base d’information de la théorie du choix social, welfarisme dont la critique a constitué un des points de départ de l’élaboration du concept de capabilité, supposé intégrer des dimensions à la fois objectives et subjectives du bien-être (well-being) des agents. Afin d’amorcer une possible réconciliation de ces deux approches, nous proposons dans un premier temps de discuter l’attribution des préférences aux individus dans le cadre conceptuel de la théorie du choix social, en nous appuyant sur les textes collectés de Kenneth Arrow. Nous défendons l’hypothèse selon laquelle l’attribution des préférences à des « positions » serait plus cohérente avec les intentions à l’origine de la théorie du choix social. Dans un second temps, nous analyserons le concept de « préférence » utilisé dans la théorie du choix social afin de montrer qu’il peut être réinterprété en termes de « jugements de valeur comparatifs », ce qui lui ôte sa connotation arbitraire. De tels jugements de valeur pourraient être construits dans l’espace des capabilités, et plus exactement des états sociaux décrits en termes de capabilités. En réinscrivant l’évaluation des capabilités dans une interprétation possible du cadre conceptuel de la théorie du choix social, nous espérons préciser l’ « approche comparative » qu’Amartya Sen oppose à l’ « approche transcendantale » dans The Idea of Justice, et amorcer une réflexion, non pas sur une théorie de la justice des capabilités, mais sur une théorie démocratique des capabilités.

GIF

  • lundi 26 novembre 2012 , 14h15 à 15h45

Intervenant Jean-Pascal Gayant - Université du Maine, GAINS
Invité par / invited by Nicolas Le Pape
Thème / Subject Economie du Sport
Titre / title From income inequality to competitive imbalance measurement : can a regressive transfer be desirable ?
Co-auteurs/Joint work with Nicolas Le Pape - CREM CNRS, Université de Caen Basse-Normandie
Résumé / abstract In this study, we investigate the use of inequality measures to assess the level of « competitive imbalance » in professional sports leagues. The analogy between the measurement of income inequality and the extent of the competitive imbalance leads to resort to measures such as Generalized Entropy and Atkinson inequality indices. We propose an axiom specific to the issue of competitive imbalance which is built on the principle of climbing a block of perfectly balanced teams in the final ranking of teams. Such an ascent arises both from several egalitarian transfers and from a regressive transfer. We suggest that such mix of transfers is « desirable » and that its impact on the index of competitive imbalance must be unambiguously a decrease. We then show that only a particular class of Generalized Entropy measures satisfies the desired axiom and we discuss the relevance of the analogy between the notions of aversion to inequality in a society and aversion to imbalance in a league.

GIF

  • lundi 19 novembre 2012 , 14h15 à 15h45

Intervenant Fabien Moizeau - CREM CNRS, Université de Rennes 1
Invité par / invited by Jean-Pascal Guironnet
Thème / Subject Economie Publique Locale, Stratification endogène
Titre / title Endogenous Income Distribution and Stratification in Economies with a Local Public Good
Co-auteurs/Joint work with David Bardey - (Universidad de Los Andes)
Co-auteurs/Joint work with Fernando Jaramillo - (Universidad del Rosario)
Résumé / abstract We develop a multijurisdiction model where individuals are heterogenous with respect to their productivity level. The key feature of the framework is that before moving to a particular jurisdiction where the amount of local public good is determined by the median voter, individuals choose their level of labor supply. Our findings suggest that the equilibrium is productivity-stratified, i.e. jurisdictions are inhabited by individuals with similar productivity. Further, the equilibrium income distribution is characterized by discontinuities, each one corresponding to a change in jurisdiction membership. It turns out that two individuals who are close in the productivity ladder may earn dramatically different labor incomes if they do not reside in the same jurisdiction. We also study the planner’s problem and characterize optimal allocations. Finally, we study the design of the tax structure that implements optimal allocations in spite of the asymmetric information. In particular, the optimal tax structure is such that externalities generated by free mobility of individuals are internalized.

GIF

  • lundi 12 novembre 2012 , 14h15 à 15h45

Intervenant Clémence Christin - CREM CNRS, Université de Caen Basse-Normandie
Invité par / invited by Séminaire interne
Thème / Subject Vertical Contracting, Entry Deterrence, Overbuying
Titre / title Equilibrium Strategic Overbuying
Co-auteurs/Joint work with Eric Avenel - CREM CNRS, Université de Rennes 1
Résumé / abstract We consider two firms competing both to sell their output and purchase their input from an upstream firm, to which they offer non-linear contracts. Firms may engage in strategic overbuying, purchasing more of the input when the supplier is capacity constrained than when it is not in order to exclude their competitor from the final market. Warehousing is a special case in which a downstream firm purchases more input than it uses and disposes of the rest. We show that both types of overbuying happen in equilibrium. The welfare analysis leads to ambiguous conclusions.
Lien / download WP201205.pdf

GIF

  • lundi 5 novembre 2012 , 14h15 à 15h45

Intervenant Ludovic Renou - University of Essex, UK
Invité par / invited by Maurice Salles
Thème / Subject Jeux répétés, Equilibre de Nash
Titre / title Repeated Nash Implementation
Co-auteurs/Joint work with Claudio Mezzetti - Department of Economics - University of Warwick, UK
Résumé / abstract This paper studies repeated implementation of social choice functions in environments with complete information and changing preferences. We introduce the condition of dynamic monotonicity and show that it is necessary for repeated implementation in finite as well as infinite horizon problems. With at least three agents, the conditions of dynamic monotonicity and no-veto power are sufficient. In infinite horizon problems with high enough discount factors, dynamic monotonicity implies weak efficiency in the range (Lee and Sabourian, 2011), while Maskin monotonicity implies dynamic monotonicity in finite horizon problems.
Lien / download Repeated Nash Implementation

GIF

  • lundi 22 octobre 2012 , 14h15 à 15h45

Intervenant Sara Biancini - CREM CNRS, Université de Caen Basse-Normandie
Invité par / invited by Séminaire interne
Thème / Subject Intellectual property rights protection
Titre / title Intellectual property rights protection in developing countries
Co-auteurs/Joint work with Emmanuelle Auriol (Toulouse School of Economics)
Co-auteurs/Joint work with Rodrigo Paillacar (université de Cergy-Pontoise)
Résumé / abstract "The paper studies the incentives that developing countries have to protect intellectual property rights (IPR). On the one hand, free-riding on rich countries technology reduces the investment cost in R&D. On the other hand, it yields a potential indirect cost : a firm that violates IPR cannot legally export in a country that enforces them. IPR act like a barrier to entry of the advanced economy markets. Moreover free-riders cannot prevent others to copy their own innovation. The analysis, which distinguishes between large and small developing countries,
predicts that small ones should be willing to respect IPR if they want to export
and access advanced economies markets, while large emerging countries, such as
China and India, will be more reluctant to do so as their huge domestic markets develop. Global welfare and innovation are higher under the full protection regime if the developing country does not innovate. It is higher under a partial regime if both countries have access to similar R&D technology and the developing country market is large enough. After presenting the theoretical framework, the paper offers an empirical analysis of the testable predictions of the model.
"

GIF

  • lundi 1 octobre 2012 , 14h15 à 15h45

Intervenant Anna Khmelnitskaya - St. Petersburg State University, Faculty of Applied Mathematics
Invité par / invited by Vincent Merlin
Thème / Subject Social capital, centrality, TU game, communication structure, Shapley value, Myerson value
Titre / title On 1-convexity and nucleolus of co-insurance games
Co-auteurs/Joint work with Theo Driessen, Vito Fragnelli, and Ilya Katsev
Résumé / abstract In some practical insurance situations the insurable risks are too heavy to be insured by only one company, for example environmental pollution risk. In such cases several insurance companies cooperate to share the liability and the premium. Then two important practical questions arise : which premium the insurance companies have to charge and how should they split the risk and the premium ? In Fragnelli and Marina (2004) this problem is approached from the game theoretical point of view and the so-called co-insurance game is introduced. In this paper we study the nonemptiness and the structure of the core and the nucleolus of a co-insurance game with respect to the variable premium value. If the premium is large enough the core is empty. For the premium between some critical bounds the co-insurance game appears to be 1-convex which in turn guarantees the nonemptiness of the core and, moreover, in this case the nucleolus appears to be a linear function of the premium. If 1-convexity does not apply, then for the premium below another critical number we show that a co-insurance game belongs to the class of veto-removed games and construct an efficient final algorithm for computing the nucleolus of a veto-removed game.
Lien / download On 1-convexity and nucleolus of co-insurance games

GIF