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Accueil > Séminaires réguliers > Séminaires Caen > Archives

2014-2015

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Les séminaires du CREM à Caen ont lieu habituellement salle IT002
Place de l’Esplanade, à Caen
le lundi à partir de 14h15

 

 

 

  • lundi 15 juin 2015 , 14h15 à 15h45 - Journée « Richesse, Justice et Vertu »

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  • lundi 8 juin 2015 , 14h15 à 15h45
Intervenant Régis Renault - LEDA, Université Dauphine
Invité par / invited by Vincent Merlin
Titre / title Search direction
Résumé / abstract A tractable model of pricing under directed search is proposed and integrated with a position auction for better slots (which rationalizes the consumer search order). The equilibrium search order resulting from the auction may be socially optimal or not, depending on the nature of product heterogeneity. Search is always inefficiently low because firms price out further exploration. Equilibrium product prices are such that the marginal consumer’s surplus decreases in the order of search. Consumers always find it optimal to follow the order of search that results from the auction. Equilibrium bids factor in position externalities across firms as prices and profits depend on the qualities of firms following in the sequence of ositions. We highlight the fundamental role of firm heterogeneity that characterizes markets and their performance. The search framework delivers a full-fledged integration of position auctions and pricing with sequential directed search.

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  • lundi 1 juin 2015 , 14h15 à 15h45 - Séminaire interne
Intervenant Olivier L’Haridon - CREM, Université Rennes 1
Titre / title Patience and Time Consistency in Collective Decisions
Résumé / abstract We present experimental evidence regarding individual and group decisions over time. Static and longitudinal methods are combined to test four conditions on time preferences : impatience, stationarity, age independence, and dynamic consistency. Decision making in groups should favor coordination via communication about voting intentions. We -nd that individuals are neither patient nor consistent, that groups are both patient and highly consistent, and that information exchange between participants helps groups converge to stable decisions. Finally we provide additional evidence showing that our results are driven by the speci-c role of groups and not by either repeated choices or individual preferences when choosing for other subjects.
Lien / Download 15-06-01_Lharidon_GDM5_5.pdf

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  • lundi 18 mai 2015 , 14h15 à 15h45, salle IT002
Intervenant Issofa Moyouwou - University of Yaounde, Cameroon
Invité par / invited by Vincent Merlin
Thème / Subject Positional Voting Rules
Titre / title Manipulability Comparisons of Positional Voting Rules for Large Three-Candidates Elections
Résumé / abstract Given any positional voting rule (PVR), a characterization of unstable voting situations is provided for three-candidate elections with large electorates. Our contribution to this literature concerns three aspects : (i) a comparison of PVRs via set inclusion of their corresponding sets of unstable voting situations ; (ii) a full classification of PVRs according to their ulnerability to coalitional manipulation ; and (iii) the determination of the maximal minimum size of a manipulating coalition. The attractiveness of the results obtained is that our conclusions are valid for the whole class of PVRs. It turns out that, under the Impartial Anonymous Culture (IAC), the PVR that minimizes the frequency of unstable voting situations is the plurality rule when the size of the manipulating coalition is unrestricted and the Borda rule for small manipulating coalitions.
Lien / Download 15-05-18_Moyouwou_PVR_manipulabity.pdf

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  • lundi 11 mai 2015 , 14h15 à 15h45, salle IT002
Intervenant Francis Bloch - Université Paris 1 Panthéon-Sorbonne
Titre / title Dynamic allocation of objects to queueing agents
Co-auteur/Joint work with David Cantala - El Colegio de Mexico
Résumé / abstract This paper analyzes the optimal allocation of objects which arrive sequentially to agents organized in a waiting list. Applications include the assignment of social housing, deceased donor organs and daycare slots. A mechanism is a probability distribution over all priority orders which are consistent with the waiting list. We consider three e-ciency criteria : -rst order stochastic dominance in the vector of agents’ values, the probability of misallocation and the expected waste. We show that the strict seniority order dominates uniform random order according to the two -rst criteria, and the uniform random order dominates strict priority according to the third criterion.If agents values are perfectly correlated, strict priority dominates all other probabilistic mechanisms for all agents values.
Lien / Download 15-05-11_Bloch_Cantala

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x lundi 27 avril 2015 , 14h15 à 15h45

Intervenant Xavier Wauthy - Facultés universitaires Saint-Louis, CORE
Invité par / invited by Fabrice Valognes
Thème / Subject Bertrand, Cournot, Edgeworth, product differentiation, capacity constraints
Titre / title From Bertrand to Cournot via Kreps and Scheinkman : a hazardous journey
Co-auteur/Joint work with Conal Duddy - J.E. Cairnes School of Business and Economics and the Whitaker Institute, National University of Ireland Galway, Ireland.
Résumé / abstract The mininal core of strategic decisions a firm has to make is three-fold : What to produce ? At which scale ? At what price ? A full-edged theory of oligopolistic competition should be able to embrace these three dimensions jointly. Starting from the Cournot-Bertrand dispute and the stream of research it gave birth to, this survey shows that we are far from having such a theory at our disposal today. Many papers cover two dimensions out of three and display insightful results but no paper satisfactorily addresses the complete picture. I discuss the limitations of the different approaches that have been undertaken. This discussion sets a clear agenda for further theoretical research on the oligopoly front.

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  • lundi 20 avril 2015 , 14h15 à 15h45
Intervenant Robert Philipowsky Unité de Recherche en Mathématiques, Université du Luxembourg,
Invité par / invited by Abderrahmane Ziad
Thème / Subject Asymmetric tax competition, Nash equilibrium, Evolutionary stable strategy
Titre / title Comparison of Nash and evolutionary stable equilibrium in asymmetric tax competition
Résumé / abstract We show that under suitable assumptions the evolutionary stable tax rate in asymmetric tax competition is strictly lower than all tax rates obtained in Nash equilibrium, generalizing in this way a recent result by Sano (Evolutionary and Institutional Economics Review 9 (2012), S1S23) and Wagener (International Economic Review 54 (2013), 12511264) obtained in the context of symmetric tax competition. Our assumptions are satis_ed in several models of capital and commodity tax competition.

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  • Mardi 7 avril 2015 , 14h15 à 15h45
Intervenant Ashley Piggins - J.E. Cairnes School of Business and Economics and the Whitaker Institute, National University of Ireland Galway, Ireland.
Invité par / invited by Vincent Merlin
Thème / Subject Binary evaluations, judgment aggregation, mean rule, tension, Borda.
Titre / title Aggregation of binary evaluations : a Borda-like approach
Co-auteur/Joint work with Conal Duddy - J.E. Cairnes School of Business and Economics and the Whitaker Institute, National University of Ireland Galway, Ireland.
Co-auteur/Joint work with William S. Zwicker - Department of Mathematics, Union College
Résumé / abstract We characterize a rule for aggregating binary evaluations – equivalently, dichotomous weak orders – similar in spirit to the Borda rule from the preference aggregation literature. The binary evaluation framework was introduced as a general approach to aggregation by Wilson (J. Econ. Theory 10 (1975) 63-77). In this setting we characterize the “mean rule,” which we derive from properties similar to those Young (J. Econ. Theory 9 (1974) 43-52) used in his characterization of the Borda rule. Complementing our axiomatic approach is a derivation of the mean rule using vector decomposition methods that have their origins in Zwicker (Math. Soc. Sci. 22 (1991) 187-227). Finally, we derive the mean rule from an approach to judgment aggregation recently proposed by Dietrich (Soc. Choice. Welf. 42 (2014) 873-911).
Lien / Download 15-03-30_Piggins_Aggregationofbinaryevaluations.pdf

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  • lundi 23 mars 2015 , 14h15 à 15h45
Intervenant Marie-Estelle Binet - CREM CNRS UMR 6211, Université de Rennes 1
Invité par / invited by Jean-Sébastien Pentecôte
Titre / title Specifying a Demand Function with imperfect Price Perception : The Shin’s Approach revisited
Résumé / abstract We develop an improved version of the method introduced by Shin (1985) to estimate the demand function when consumers are imperfectly informed about their pricing schedule. As Shin’s approach suits only to a double logarithmic demand function, we develop a nesting method for combining demand models reacting to average, respectively marginal prices, to provide a rationale for, and a generalization of Shin’s perceived price model. In addition to correcting Shin’s original model specification, we are also able to derive a perceived price specification for a linear expenditure demand function.
Lien / Download 15-03-23_Binetcarlevaroeare14.pdf

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  • lundi 16 mars 2015 , 14h15 à 15h45
Intervenant Robert Owen - Université de Nantes
Invité par / invited by Bernard Franck
Thème / Subject
Titre / title Rethinking the Evolutionary Foundations of Economic Analysis
Résumé / abstract

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  • lundi 9 mars 2015 , 14h15 à 15h45
Intervenant Alex Coad - University of Sussex
Invité par / invited by Jean Bonnet
Thème / Subject croissance de la firme
Titre / title Too fast to live ? Effects of growth on survival across the growth distribution
Co-auteur/Joint work with Julian S. Frankish
Co-auteur/Joint work with Richard G. Roberts
Co-auteur/Joint work with David J. Storey - University of Sussex
Résumé / abstract There are several theoretical reasons to suppose that excessive fast growth may harm survival : ‘Penrose effects’ operating through limits to managerial attention, cash flow problems, ‘time compression diseconomies’ and convex adjustment costs that make costs exceed revenues, and difficulties in quickly finding good matches on labour markets. We explore survival across the growth rate distribution using a rich dataset of a cohort of 6247 new ventures, using customer records data from a major UK bank. We measure non-survival though termination of the business account (as opposed to continuation or switching the account to a rival bank). Although growth enhances survival on average, the highest decile of the growth distribution never has the highest survival, and there are significant non-linearities (specification tests prefer a seventh-order polynomial). Our findings have implications for the current policy interest in high growth firms.

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  • lundi 2 mars 2015 , 14h15 à 15h45
Réunion AG CREM Caen

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  • lundi 9 février 2015 , 14h15 à 15h45
Intervenant Marcus Dejardin - Université de Namur
Invité par / invited by Jean Bonnet
Thème / Subject Causation ; effectuation ; environmental dynamism ; ambidexterity ; entrepreneurial orientation
Titre / title Causation and Effectuation in Turbulent Times : Conditional Impact on Entrepreneurial Orientation
Co-auteur/Joint work with Johanna Vanderstraeten, Julie Hermans, Dendi Ramdani, Arjen van Witteloostuijn
Résumé / abstract We examine whether a firm can repeatedly engage in entrepreneurial activities by following causal or effectual development strategies, and how environmental dynamism impacts these relationships. In stable environments, prior planning results in higher degrees of entrepreneurialism. Additionally, our analyses reveal interaction effects between causal and effectual development strategies. Simultaneously opting for planned logics of action and pre-commitments further stimulates the degree of entrepreneurialism. In particular network partners providing strategic advantages such as access low cost resources are of interest. Moreover, unlike in stable environments, causal strategies are not positively associated with entrepreneurialism in unstable environments.
Lien / Download http://www.uclouvain.be/cps/ucl/doc/core/documents/coredp2013_24web.pdf

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  • lundi 26 janvier 2015 , 14h15 à 15h45
Intervenant Jean-Christophe Poudou - Lameta, Université Montpellier 1
Invité par / invited by Nicolas Le Pape
Thème / Subject universal service, postal market, digitalization
Titre / title Reforming the postal universal service
Co-auteur/Joint work with Axel Gautier
Résumé / abstract The postal sector has undergone dramatic changes over the recent years under the double effect of ongoing liberalization and increased competition with alternative communication channels (e-substitution). As a result, the mail volume handled by the historical operator has declined sharply while the latter’s ability to match the same standard of universal service may be under threat. Thus, a reform of the postal universal service is on the agenda. This paper examines possible reforming options ranging from keeping universal service within the postal sector to redefining universal service as spanning postal and electronic technologies.
Lien / Download http://www.uclouvain.be/cps/ucl/doc/core/documents/coredp2013_24web.pdf

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  • lundi 19 janvier 2015 , 14h15 à 15h45
Intervenant Fabio Padovano Condorcet Center for Political Economy and CREM-CNRS, Université de Rennes 1, France
Invité par / invited by Vincent Merlin
Thème / Subject Vertical and horizontal fragmentation of government
Titre / title Historical determinants of government fragmentation : a cross country analysis
Co-auteur/Joint work with Ilaria Petrarca, Yvon Rocaboy
Résumé / abstract This paper aims to explain the large differences in the number of local jurisdictions and of government levels across the countries of the world by looking at how historical events shape the populations’ preferences for general public goods, more efficiently provided by higher tiered, larger jurisdictions, and local public goods, better supplied by smaller, lower tiered jurisdictions. Previous analyses explained these influences away by using fixed effects specifications. We instead find that a history of foreign invasions decreases the number of local jurisdictions and raises the number of government tiers, the same effect found for internal risks such as natural calamities. The shape of the land and linguistic fragmentation also generate preferences for local goods and increases horizontal fragmentation. The type of government also matters, as dictatorial regimes are flatter and less fragmented than democracies. All these results mark significant innovations with respect to the literature that explained government fragmentation only in terms of country size, population and preferences for accountability.

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  • lundi 15 décembre 2014 , 14h15 à 15h45 - Séminaire interne
Intervenant Ibrahima Dia - CREM, Université Caen Basse-Normandie
Thème / Subject Entrepreneuriat
Titre / title Les déterminants de l’entrepreneuriat féminin dans le secteur informel au Sénégal
Résumé / abstract Reasoning on multiple criteria is a key issue in group decision to take into account the multidimensional nature of real-world decision-making problems. In order to reduce the induced information overload, in multicriteria decision analysis, criteria are in general aggregated, in many cases by a simple discriminant function of the form of a weighted sum. It requires to, a priori and completely, elicit preferences of decision makers. That can be quite arbitrary. In everyday life, to reduce information overload people often use a heuristic, called “Take-the-best” : they take criteria in a predefined order, the first criterion which discriminates the alternatives at stake is used to make the decision. Although useful, the heuristic can be biased. This article proposes the Logical Multicriteria Sort process to support multicriteria sorting within islands of agreement. It therefore does not require a complete and consistent a priori set of preferences, but rather supports groups to quickly identify the criteria for which an agreement exists. The process can be seen as a generalization of Take-the-best. It also proposes to consider one criterion at a time but once a criterion has been found discriminating it is recorded, the process is iterated and relevant criteria are logically combined. Hence, the biases of Take-the-best are reduced. The process is supported by a GDSS, based on Logical Information Systems, which gives instantaneous feedbacks of each small decision and keeps tracks of all of the decisions taken so far. The process is incremental, each step involves low information load. It guarantees some fairness because all considered alternatives are systematically analyzed along the selected criteria. A successful case study is reported.

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  • lundi 8 décembre 2014 , 14h15 à 15h45
Intervenant Mireille Ducassé - IRISA, INSA Rennes
Invité par / invited by Vincent Merlin
Thème / Subject
Titre / title Computer sciences, group decision and negotiation
Résumé / abstract Reasoning on multiple criteria is a key issue in group decision to take into account the multidimensional nature of real-world decision-making problems. In order to reduce the induced information overload, in multicriteria decision analysis, criteria are in general aggregated, in many cases by a simple discriminant function of the form of a weighted sum. It requires to, a priori and completely, elicit preferences of decision makers. That can be quite arbitrary. In everyday life, to reduce information overload people often use a heuristic, called “Take-the-best” : they take criteria in a predefined order, the first criterion which discriminates the alternatives at stake is used to make the decision. Although useful, the heuristic can be biased. This article proposes the Logical Multicriteria Sort process to support multicriteria sorting within islands of agreement. It therefore does not require a complete and consistent a priori set of preferences, but rather supports groups to quickly identify the criteria for which an agreement exists. The process can be seen as a generalization of Take-the-best. It also proposes to consider one criterion at a time but once a criterion has been found discriminating it is recorded, the process is iterated and relevant criteria are logically combined. Hence, the biases of Take-the-best are reduced. The process is supported by a GDSS, based on Logical Information Systems, which gives instantaneous feedbacks of each small decision and keeps tracks of all of the decisions taken so far. The process is incremental, each step involves low information load. It guarantees some fairness because all considered alternatives are systematically analyzed along the selected criteria. A successful case study is reported.

GIF

 

  • lundi 1 décembre 2014 , 14h15 à 15h45
Intervenant Etienne Farvaque - EDEHN, Université du Havre
Invité par / invited by Abderrahmane Ziad
Titre / title FOMC Members’ Incentives to Disagree : Regional Motives and Background Influences

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  • lundi 24 novembre 2014 , 14h15 à 15h45
Intervenant Noemi Navarro - Facultad de Ciencias Económicas y Empresariales, Bilbao
Invité par / invited by Vincent Merlin
Titre / title Forward-looking Network Formation 
Résumé / abstract We consider situations where players extract utility from different network relations among them. Time is discrete and players perceive the evolution of the network through time as a stationary transition probability matrix, where probabilities can differ from one player to another, and therefore are subjective. Players have stationary VNM preferences over each possible network structure and discount the future. A system of transition probability matrices and discount factors is called a forward-looking network formation scheme if, first, the probability that a link is created is positive if the discounted expected utility gains to its two participants are positive, and if, second, the probability that a link is eliminated is positive if the discounted, expected utility gain to at least one of its two participants is positive. We show that a forward-looking network formation scheme where agents have different discount factors and different positive transition probabilities always exists. These transition probabilities, whenever positive, are increasing in the corresponding discounted, expected utility gains. Whenever there is a forward-looking network formation scheme with different discount factors and different positive transition probabilities, we can find a common discount factor and a common transition probability matrix for all players that are a forward-looking network formation scheme as well. This common transition probability matrix has the same long-run support as the original forward-looking network formation scheme, meaning that the Markov chain defined by all these matrices converges to the same set of stable networks or cycle of networks, but can differ in the limiting probabilities. The existence result is finally extended when agents are allowed to redistribute payoffs in discounted expected terms according to a linear rule.

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  • lundi 17 novembre 2014 , 14h15 à 15h45
Intervenant José de Sousa - Université Paris-Sud, RITM
Invité par / invited by Clémence Christin
Thème / Subject Commerce international
Titre / title Export Decision under Risk
Co-auteur/Joint work with Anne-Célia Disdier - PSE, INRA
Co-auteur/Joint work with Carl Gaigné - INRA, UMR SMART

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  • lundi 3 novembre 2014 , 14h15 à 15h45
Réunion Directeurs de thèse

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  • lundi 13 octobre 2014 , 14h15 à 15h45, Salle 119
Intervenant Ivan Ledezma - Université de Bourgogne
Invité par / invited by Sara Biancini
Thème / Subject Commerce international
Titre / title Trade Liberalisation and Heterogeneous Technology Investments
Co-auteur/Joint work with Maria Bas - CEPII
Résumé / abstract

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  • lundi 29 septembre 2014 , 14h15 à 15h45
Intervenant Vincent Iehlé - PSL, Université Paris-Dauphine, LEDa & CEREMADE
Invité par / invited by Sara Biancini
Thème / Subject School Choice, Hall’s marriage theorem, stable matching, zoning policy, Pareto improvement
Titre / title Two-Sided Matching with One-Sided Preferences
Co-auteur/Joint work with Guillaume Haeringer - Baruch College
Résumé / abstract In a school choice context we show that considering only schools’ priorities and the set of acceptable schools for each student —but not how these schools are ranked in their preferences— we can restrict the set of possible stable matchings that can arise for any preference profile of the students that leaves the set of acceptable schools unchanged. We characterize impossible matches, i.e., of pairs student-school that cannot be matched at any stable matching, for any preference profile. Our approach consists of linking Hall’s marriage condition to stable matchings. Our results offer a new methodology to assess to what extent the preferences on one side of a matching market can preset the stable matchings that can emerge. First, we use this technique to discuss the impact of priority zoning in school choice problems. Second, a new mechanism for school choice problems is proposed. It is shown that it (weakly) Pareto dominates the Student Optimal Stable Mechanism and retain some of its incentives.

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Intervenant Bourheneddine Ben Dhaou - Doctorant du CREM, Université de Caen Basse-Normandie
Invité par / invited by Séminaire interne
Thème / Subject Jeux coopératifs
Titre / title Résolution des jeux hédoniques sous forme extensive : une analyse stratégique
Lien / download 13_11_18_Ben Dhaou.pdf

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  • lundi 4 novembre 2013 , 14h15 à 15h45
Intervenant Jan Van Hove - University of Leuven, HU Brussels and INFER
Invité par / invited by Sophie Lecostey
Thème / Subject International trade
Titre / title Export Survival, Differentiation and Returning to Exports
Co-auteur/Joint work with Filip Abraham - University of Leuven and Vlerick Business School
Co-auteur/Joint work with Zuzanna Studnicka - University of Leuven
Résumé / abstract Studying a unique data set of Belgian firm level manufacturing exports, and distinguishing between firms, products and destinations, we find that the median and average duration of exports are short. Export survival is positively affected, both in the short and in the long run, by firm size and product and geographic diversification. However, the latter finding is reversed when looking at the exports of specific products to specific markets. In addition, returning to exports increases the probability of export survival. Hence there appears to be a learning effect as firms benefit from their previous experience exporting particular goods or exporting to particular markets. Therefore, the fixed cost of exporting is not sunk, contradicting theoretical assumptions.

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  • lundi 14 octobre 2013 , 14h15 à 15h45
Intervenant Emmanuel Peterlé - CREM, Université de Rennes 1
Invité par / invited by Jean-Pascal Guironnet
Titre / title College major choice, occupational segregation and gender wage gap
Résumé / abstract Although women have caught up with men in terms of educational attainment in most industrialized countries, they still largely differ in the content of study. In this paper, we investigate to what extent gender segregation in fields of study affects both gender occupational segregation and gender wage gap. We use therefore French data from the “Enquête Emploi” survey. Our findings suggest that women and men differing in field of study significantly impacts occupational segregation in the labor market. It does not however play a significant role in the gender wage differentials. Our data also shows that gender earnings differential within predominantly female occupations could be largely explained by structural differences in characteristics. This is not the case in predominantly male jobs, suggesting the potential existence of discriminatory practices in these occupations.
Lien / download 13_10_14_Peterle.pdf

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  • lundi 30 septembre 2013 , 14h15 à 15h45
Intervenant William Zwicker - Department of Mathematics, Union College, Schenectady NY, USA
Invité par / invited by Vincent Merlin
Titre / title Condorcet vs Borda, round n+1
Lien / download Abstract

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