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Freedom of Choice between Unitary and Two-Tier Boards: An Empirical Analysis
No full textWe examine board structure in France, which since 1966 has allowed firms freedom to choose between unitary and two-tier boards. We analyze how this choice relates to characteristics of the firm and its environment. Firms with severe asymmetric information tend to opt for unitary boards; firms with a potential for private benefits extraction tend to adopt two-tier boards. There is enhanced sensitivity of CEO turnover to performance at firms with two-tier boards, indicating greater monitoring. Our results are broadly consistent with the Adams and Ferreira (2007) model and suggest there are gains from allowing freedom of contract about board structure.nonouirechercheInternationa
Prepayment option of a perpetual corporate loan: the impact of the funding costs
No full textWe investigate in this paper a perpetual prepayment option related to a corporate loan. The short interest rate and default intensity of the firm are supposed to follow CIR processes. A liquidity term that represents the funding costs of the bank is introduced and modeled as a continuous time discrete state Markov chain. The prepayment option needs specific attention as the payoff itself is a derivative product and thus an implicit function of the parameters of the problem and of the dynamics. We prove verification results that allows to certify the geometry of the exercise region and compute the price of the option. We show moreover that the price is the solution of a constrained minimization problem and propose a numerical algorithm building on this result. The algorithm is implemented in a two-dimensional code and several examples are considered. It is found that the impact of the prepayment option on the loan value is not to be neglected and should be used to assess the risks related to client prepayment. Moreover the Markov chain liquidity model is seen to describe more accurately clients' prepayment behavior than a model with constant liquidity.nonnonouirechercheInternationa
Guest Editors’ Introduction
No full textThis special issue presents a selection of papers in Knowledge Representation (KR) in Artificial Intelligence (AI), intended to illustrate the depth and breadth of current research in the area.nonouirechercheInternationa
Measuring the Liquidity Part of Volume
No full textBased on the concept that the presence of liquidity frictions can increase the daily traded volume, we develop an extended version of the mixture of distribution hypothesis model (MDH) along the lines of Tauchen and Pitts (1983) to measure the liquidity portion of volume. Our approach relies on a structural definition of liquidity frictions arising from the theoretical framework of Grossman and Miller (1988), which explains how liquidity shocks affect the way in which information is incorporated into daily trading characteristics. In addition, we propose an econometric setup exploiting the volatility–volume relationship to filter the liquidity portion of volume and infer the presence of liquidity frictions using daily data. Finally, based on FTSE 100 stocks, we show that the extended MDH model proposed here outperforms that of Andersen (1996) and that the liquidity frictions are priced in the cross-section of stock returns.nonouirechercheInternationa
Peut-on prédire la consommation des 50-65 ans à partir du critère du Bien Vieillir Désiré ?
No full textLes 50-65 ans forment aujourd’hui la tranche d’âge la plus attractive pour le marketing des seniors. Constatant le caractère hétérogène du vieillissement qui les affecte et l’importance du Bien Vieillir pour la société, nous testons la pertinence du critère du Bien Vieillir Désiré pour expliquer leur consommation. Une analyse typologique permet de confirmer a posteriori son rôle prédictif et de préciser la nature de son influence sur la constitution de 4 profils (les prévoyants aisés, les passifs insatisfaits, les mitigés, les bien-vieillissants). En découlent des recommandations pour aider les entreprises à faire de ce critère un levier de croissance.50-65 years old people have become the most attractive target for Marketing to Seniors. As ageing is heterogeneous among them and as Aging Well is now a major societal issue, we investigate the relevance of Desired Aging Well to explain their consumption. Cluster analysis is used to confirm a posteriori its predictive role and clarify the nature of its influence on the formation of 4 profiles (the wealthy far sighted, the dissatisfied passives, the lukewarm and the well-aging). Finally, managerial recommendations are suggested to help companies to use this criterion as a growth engine.nonouirechercheNationa
Exploring Market Uncertainty: Some Methodological Challenges
No full text“Fundamental assumptions about the business need to be changed. (…) People were so busy working on the nuts and bolts of the reorganization, we failed to step back and assess how the world was changing around us.” (Raytheon’s CEO, 1999) This is one of many quotes that translate the doubts that can arise and be formulated when market dynamics are controverted, when markets become riddled with ambiguities and transform into “hot situations” (Callon, 1998). The paper aims to discuss the methodological challenges raised by the observation and analysis of such uncertain situations. It starts with three assumptions on the nature of markets. 1° Markets are sociotechnical agencements of theories, practices, and devices. 2° Markets are performed by the relations between these three entities. 3° Markets are an ongoing and uncertain process of framing and overflowing of these relations. Such assumptions are in line with Actor-Network Theory but differ from classical studies on markets. First, we extend the ontology of markets participants both to human and non-human beings (Callon, 1986). Second, while some works focus on the stability of markets shaped by power structures (Fligstein, 2002) or technical determinism (David, 1985), we put the stress on the doubts of market actors and the intertwining of the language-games that they generate (Depeyre & Dumez, 2008). Third, while some approaches consider an already existing state of the world, we explore the market in the making (Callon, 1998). In line with this framework, the paper articulates four methodological propositions: P1. Studying controversies. They are critical moments during which people make sense of a situation by confronting their interests, their beliefs, or their values, and, by doing so, are elaborating social facts (Latour, 1988). This principle aims at capturing the performative dimension of markets (MacKenzie et al. 2007). P2. Following the actors. As controversies develop, actors exchange arguments, use material devices and deploy strategies. They carry out a triple inventory of the market (Callon et al., 2009): they define the interests, the identity, and the role of market’s participants; they connect problems under discussion and other problems with which some committed groups strive to establish links; they explore some unexpected solutions. This principle aims at respecting the uncertainty of markets. P3. Adopting methodological pluralism. Who wants to follow the actors needs to be mobile. It leads researchers to use various sources and types of data. This principle aims at capturing the heterogeneous relations linking theories, practices, and market devices. P4. Narrating the market. The inquiry produces a narrative that 1° highlights theories, practices, and market devices, 2° reveals the doubts that are raised, and 3° identifies the turning points (Abbott, 2001) shaping the market process. This principle aims at respecting the complexity of the market process. We thus propose to study controversies not as isolated moments, but as narrative events that make markets. Each proposition is discussed and illustrated with examples from a case study about the US defense industry (a context where market participants have facednonouirechercheInternationa
Apports méthodologiques du courant néo-structural à l’agenda de recherche du « travail institutionnel »
No full textLe programme de recherche du travail institutionnel accorde une place importante à la notion d’agence et à la réflexivité des acteurs à travers leur capacité de représentation de l'institution où ils sont encastrés. Il essaie également d'intégrer la dimension relationnelle dans l'étude de l'activité des individus et des collectifs. L’agenda de recherche de l’institutional work s’inscrit dans une filiation critique du courant néo-institutionnaliste dont il conteste la tendance à réduire le comportement des acteurs à une sorte de passivité mimétique et la dévaluation des dynamiques collectives et politiques (Huault et Leca, 2009). La perspective cognitive demeure néanmoins prégnante dans les articles fondateurs de ce courant de recherche ainsi que dans les articles empiriques qui se sont inspirés de l'analyse du travail institutionnel.Nous considérons, pour notre part, que la sociologie néo-structurale, de par sa perspective relationnelle, peut compléter les études portant sur le travail institutionnel. Cette approche sociologique met en évidence l'importance des interdépendances entre acteurs en les formalisant grâce aux techniques d'analyse de réseaux. Celles-ci permettent de montrer l'importance ou pas des acteurs centraux ou périphériques et mettent en valeur la prédominance de telle ou telle structure relationnelle qui favoriserait une forme particulière de travail institutionnel (création, maintien ou déstabilisation) et les processus d'institutionnalisation ou de désinstitutionnalisation des règles ou normes dans un champ déterminé. Cette communication se propose de mettre en relief les apports méthodologiques pouvant être offerts par la sociologie néo-structurale au décryptage des processus de travail institutionnel. Dans une première partie, l’article cherche à décrire les fondements de l’approche de l’institutional work en l’inscrivant dans le sillage critique du néo-institutionnalisme. Loin de refléter la seule instrumentalisation des institutions par des acteurs-stratèges, la perspective du travail institutionnel proposée par Lawrence et Suddaby (2006) donne à voir la dynamique collective inhérente au processus d’institutionnalisation (ou de désinstitutionnalisation), de légitimation (ou de délégitimation) de règles, normes et pratiques. Au travers de la notion de « travail », l’attention se focalise désormais sur le flux d’actions, multiples et souvent rivales, entreprises par les acteurs individuels, groupaux ou organisés, en vue de créer, consolider, détruire, bricoler, transformer les institutions. La mise en exergue des notions d'effort et d'intentionnalité s’accompagne ainsi d’une redéfinition du concept d’agence et d’un réexamen de la relation entre agence et institutions. Puis, on souligne le recentrage autour de la dimension relationnelle que le courant de l’institutional work opère. Dans une seconde partie, l’article se penche sur les apports potentiels de l’outillage méthodologique de la social network analysis à l’analyse du travail institutionnel. Il met en relief la manière dont la méthodologie néo-structurale pourrait enrichir l’analyse des dynamiques collective, dynamiques et multi-niveaux à l’œuvre dans les processus socio-politiques inhérents au travail institutionnel.nonouirechercheNationa
Fast algorithms for min independent dominating set
No full textWe first devise a branching algorithm that computes a minimum independent dominating set with running time O∗(1.3351n)=O∗(20.417n)O∗(1.3351n)=O∗(20.417n) and polynomial space. This improves upon the best state of the art algorithms for this problem. We then study approximation of the problem by moderately exponential time algorithms and show that it can be approximated within ratio 1+ϵ1+ϵ, for any ϵ>0ϵ>0, in a time smaller than the one of exact computation and exponentially decreasing with ϵϵ. We also propose approximation algorithms with better running times for ratios greater than 3 in general graphs and give improved moderately exponential time approximation results in triangle-free and bipartite graphs. These latter results are based upon a new bound on the number of maximal independent sets of a given size in these graphs, which is a result interesting per se.nonouirechercheInternationa
UCD : Upper confidence bound for rooted directed acyclic graphs
No full textIn this paper we present a framework for testing various algorithms that deal with transpositions in Monte-Carlo Tree Search (MCTS). We call this framework Upper Confidence bound for Direct acyclic graphs (UCD) as it constitutes an extension of Upper Confidence bound for Trees (UCT) for Direct acyclic graphs (DAG).When using transpositions in MCTS, a DAG is progressively developed instead of a tree. There are multiple ways to handle the exploration exploitation dilemma when dealing with transpositions. We propose parameterized ways to compute the mean of the child, the playouts of the parent and the playouts of the child. We test the resulting algorithms on several games. For all games, original configurations of our algorithms improve on state of the art algorithms.nonouirechercheInternationa
Aggregating Conditionally Lexicographic Preferences on Multi-issue Domains
No full textOne approach to voting on several interrelated issues consists in using a language for compact preference representation, from which the voters’ preferences are elicited and aggregated. A language usually comes with a domain restriction. We consider a well-known restriction, namely, conditionally lexicographic preferences, where both the relative importance between issues and the preference between values of an issue may depend on the values taken by more important issues. The naturally associated language consists in describing conditional importance and conditional preference by trees together with conditional preference tables. In this paper, we study the aggregation of conditionally lexicographic preferences, for several voting rules and several restrictions of the framework. We characterize computational complexity for some popular cases, and show that in many of them, computing the winner reduces in a very natural way to a maxsat problem.nonouirechercheInternationa