848 resultados para Kalai, Ehud. Rational learning lead to Nash equilibrium
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The rationalizability of a choice function on an arbitrary domain under various coherence properties has received a considerable amount of attention both in the long-established and in the recent literature. Because domain closedness conditions play an important role in much of rational choice theory, we examine the consequences of these requirements on the logical relationships among different versions of rationalizability. It turns out that closedness under intersection does not lead to any results differing from those obtained on arbitrary domains. In contrast, closedness under union allows us to prove an additional implication.
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La délégation du pouvoir de gestion aux administrateurs et aux gestionnaires, une caractéristique intrinsèque à la gestion efficace de grandes entreprises dans un contexte de capitalisme, confère une grande discrétion à l’équipe de direction. Cette discrétion, si elle n’est pas surveillée, peut mener à des comportements opportunistes envers la corporation, les actionnaires et les autres fournisseurs de capital qui n’ont pas de pouvoir de gestion. Les conflits entre ces deux classes d’agents peuvent émerger à la fois de décisions de gouvernance générale ou de transactions particulières (ie. offre publique d’achat). Dans les cas extrêmes, ces conflits peuvent mener à la faillite de la firme. Dans les cas plus typiques, ils mènent l’extraction de bénéfices privés pour les administrateurs et gestionnaires, l’expropriation des actionnaires, et des réductions de valeur pour la firme. Nous prenons le point de vue d’un petit actionnaire minoritaire pour explorer les méchanismes de gouvernance disponibles au Canada et aux États‐Unis. Après une synthèse dans la Partie 1 des théories sous‐jacentes à l’étude du pouvoir dans la corporation (séparation de la propriété et du contrôle et les conflits d’agence), nous concentrons notre analyse dans la Partie 2 sur les différents types de méchanismes (1) de gouvernance interne, (2) juridiques et (3) marchands, qui confèrent du pouvoir aux deux classes d’agents. Nous examinons comment les intérêts de ces deux classes peuvent être réalignés afin de prévenir et résoudre les conflits au sein de la firme. La Partie 3 explore un équilibre dynamique de pouvoir corporatif qui cherche à minimiser le potentiel d’opportunisme toute en préservant une quantité de discrétion suffisante pour la gestion efficace de la firme. Nous analysons des moyens pour renforcer les protections des actionnaires minoritaires et proposons un survol des pistes de réforme possibles.
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Les tendances de la participation à la formation des adultes au Canada n’ont pas évolué depuis des décennies, malgré les nouvelles influences économiques qui ont stimulé l’augmentation et la diversification permanente de la formation des employés et malgré les initiatives plus nombreuses en faveur de l’apprentissage des employés en milieu de travail. Il est donc nécessaire de ne plus se contenter d’étudier les prédicteurs de la formation déjà connus dans les profils des employés et des employeurs. Il est, en revanche, indispensable d’étudier les antécédents de la participation des employés à la formation, y compris les aspects et les étapes du processus qui la précède. Cette étude porte sur les antécédents de la participation des employés aux formations dans un important collège communautaire urbain en Ontario. Afin de préparer le recueil des données, un cadre théorique a été élaboré à partir du concept d’expression de la demande. Ce cadre implique l’existence d’un processus qui comporte plusieurs étapes, au cours desquelles plusieurs intervenants interagissent et dont la formation est susceptible d’être le résultat. Les résultats de l’enquête sur le profil d’apprentissage ont permis de conclure que le comportement des employés et de l’employeur est conforme aux modèles de prédicteurs existants et que les taux et les types de participation étaient similaires aux tendances nationales et internationales. L’analyse des entrevues d’un groupe d’employés atypiques, de leurs superviseurs, ainsi que de représentants du collège et du syndicat, a révélé d’importants thèmes clés : l’expression de la demande n’est pas structurée et elle est communiquée par plusieurs canaux, en excluant parfois les superviseurs. De plus, la place de l’auto évaluation est importante, ainsi que la phase de prise de décision. Ces thèmes ont souligné l’interaction de plusieurs intervenants dans le processus d’expression de la demande d’apprentissage et pendant la prise de décision. L’examen des attentes de chacun de ces intervenants au cours de ce processus nous a permis de découvrir un désir tacite chez les superviseurs et les employés, à savoir que la conversation soit à l’initiative de « l’autre ». Ces thèmes clés ont été ensuite abordés dans une discussion qui a révélé une discordance entre le profil de l’employeur et les profils des employés. Celle-ci se prête à la correction par l’employeur de son profil institutionnel pour l’harmoniser avec le profil dispositionnel des employés et optimiser ainsi vraisemblablement son offre de formation. Ils doivent, pour cela, appliquer un processus plus systématique et plus structuré, doté de meilleurs outils. La discussion a porté finalement sur les effets des motivations économiques sur la participation des employés et a permis de conclure que, bien que les employés ne semblent pas se méfier de l’offre de formation de l’employeur et que celle ci ne semble pas non plus les décourager, des questions de pouvoir sont bel et bien en jeu. Elles se sont principalement manifestées pendant le processus de prise de décision et, à cet égard, les superviseurs comme les employés reconnaissent qu’un processus plus structuré serait bénéfique, puisqu’il atténuerait les problèmes d’asymétrie et d’ambiguïté. Les constatations de cette étude sont pertinentes pour le secteur de la formation des adultes et de la formation en milieu de travail et, plus particulièrement, pour la méthodologie de recherche. Nous avons constaté l’avantage d’une méthodologie à deux volets, à l’écoute de l’employeur et des employés, afin de mieux comprendre la relation entre l’offre de formation et la participation à la formation. La définition des antécédents de la participation sous la forme d’un processus dans lequel plusieurs intervenants remplissent plusieurs rôles a permis de créer un modèle plus détaillé qui servira à la recherche future. Ce dernier a démontré qu’il est indispensable de reconnaître que la prise de décision constitue une étape à part entière, située entre l’expression de la demande et la participation à la formation. Ces constatations ont également révélé qu’il est véritablement indispensable que le secteur de la formation des adultes continue à traiter les questions reliées à la reconnaissance de la formation informelle. Ces conclusions et la discussion sur les constatations clés nous ont inspiré des recommandations à appliquer pour modifier les retombées du processus précédant la participation des employés à la formation. La majorité de ces recommandations ont trait à l’infrastructure de ce processus et ciblent donc principalement l’employeur. Certaines recommandations sont cependant destinées aux syndicats, aux superviseurs et aux employés qui peuvent aider l’employeur à remplir son rôle et favoriser la participation efficace de tous à ce processus. Les recommandations qui précédent impliquent que ce sont les antécédents de la formation qui gagneraient à être plus structurés et non la formation elle même. La structuration de l’infrastructure de l’apprentissage présente cependant des risques à elle seule. En liaison avec ce phénomène, une étude spécifique des effets de la nature, de la qualité et de l’asymétrie de la relation superviseur employé sur la participation des employés à la formation serait bénéfique. Mots clés : formation en entreprise, formation professionnelle continue, antécédents à la participation, employés de soutien
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This paper examines a dynamic game of exploitation of a common pool of some renewable asset by agents that sell the result of their exploitation on an oligopolistic market. A Markov Perfect Nash Equilibrium of the game is used to analyze the effects of a merger of a subset of the agents. We study the impact of the merger on the equilibrium production strategies, on the steady states, and on the profitability of the merger for its members. We show that there exists an interval of the asset's stock such that any merger is profitable if the stock at the time the merger is formed falls within that interval. That includes mergers that are known to be unprofitable in the corresponding static equilibrium framework.
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We investigate the properties of feedforward neural networks trained with Hebbian learning algorithms. A new unsupervised algorithm is proposed which produces statistically uncorrelated outputs. The algorithm causes the weights of the network to converge to the eigenvectors of the input correlation with largest eigenvalues. The algorithm is closely related to the technique of Self-supervised Backpropagation, as well as other algorithms for unsupervised learning. Applications of the algorithm to texture processing, image coding, and stereo depth edge detection are given. We show that the algorithm can lead to the development of filters qualitatively similar to those found in primate visual cortex.
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We propose a nonparametric method for estimating derivative financial asset pricing formulae using learning networks. To demonstrate feasibility, we first simulate Black-Scholes option prices and show that learning networks can recover the Black-Scholes formula from a two-year training set of daily options prices, and that the resulting network formula can be used successfully to both price and delta-hedge options out-of-sample. For comparison, we estimate models using four popular methods: ordinary least squares, radial basis functions, multilayer perceptrons, and projection pursuit. To illustrate practical relevance, we also apply our approach to S&P 500 futures options data from 1987 to 1991.
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Blogging has become one of the key ingredients of the so-called socials networks. This phenomenon has indeed invaded the world of education. Connections between people, comments on each other posts, and assessment of innovation are usually interesting characteristics of blogs related to students and scholars. Blogs have become a kind of new form of authority, bringing about (divergent) discussions which lead to creation of knowledge. The use of blogs as an innovative, educational tool is not at all new. However, their use in universities is not very widespread yet. Blogging for personal affairs is rather commonplace, but blogging for professional affairs – teaching, research and service, is scarce, despite the availability of ready-to-use, free tools. Unfortunately, Information Society has not reached yet enough some universities: not only are (student) blogs scarcely used as an educational tool, but it is quite rare to find a blog written by University professors. The Institute of Computational Chemistry of the University of Girona and the Department of Chemistry of the Universitat Autònoma de Barcelona has joined forces to create “InnoCiència”, a new Group on Digital Science Communitation. This group, formed by ca. ten researchers, has promoted the use of blogs, twitters. wikis and other tools of Web 2.0 in activities in Catalonia concerning the dissemination of Science, like Science Week, Open Day or Researchers’ Night. Likewise, its members promote use of social networking tools in chemistry- and communication-related courses. This communication explains the outcome of social-network experiences with teaching undergraduate students and organizing research communication events. We provide live, hands-on examples and interactive ground to show how blogs and twitters can be used to enhance the yield of teaching and research. Impact of blogging and other social networking tools on the outcome of the learning process is very depending on the target audience and the environmental conditions. A few examples are provided and some proposals to use these techniques efficiently to help students are hinted
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Looks at some of the models of learning and discusses how they apply to university students
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This paper studies oligopolistic competition in education markets when schools can be private and public and when the quality of education depends on ìpeer groupî e§ects. In the Örst stage of our game schools set their quality and in the second stage they Öx their tuition fees. We examine how the (subgame perfect Nash) equilibrium allocation (qualities, tuition fees and welfare) is a§ected by the presence of public schools and by their relative position in the quality range. When there are no peer group e§ects, e¢ ciency is achieved when (at least) all but one school are public. In particular in the two school case, the impact of a public school is spectacular as we go from a setting of extreme di§erentiation to an e¢ cient allocation. However, in the three school case, a single public school will lower welfare compared to the private equilibrium. We then introduce a peer group e§ect which, for any given school is determined by its student with the highest ability. These PGE do have a signiÖcant impact on the results. The mixed equilibrium is now never e¢ cient. However, welfare continues to be improved if all but one school are public. Overall, the presence of PGE reduces the e§ectiveness of public schools as regulatory tool in an otherwise private education sector.
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In this paper, we employ techniques from artificial intelligence such as reinforcement learning and agent based modeling as building blocks of a computational model for an economy based on conventions. First we model the interaction among firms in the private sector. These firms behave in an information environment based on conventions, meaning that a firm is likely to behave as its neighbors if it observes that their actions lead to a good pay off. On the other hand, we propose the use of reinforcement learning as a computational model for the role of the government in the economy, as the agent that determines the fiscal policy, and whose objective is to maximize the growth of the economy. We present the implementation of a simulator of the proposed model based on SWARM, that employs the SARSA(λ) algorithm combined with a multilayer perceptron as the function approximation for the action value function.
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An example of the evolution of the interacting behaviours of parents and progeny is studied using iterative equations linking the frequencies of the gametes produced by the progeny to the frequencies of the gametes in the parental generation. This population genetics approach shows that a model in which both behaviours are determined by a single locus can lead to a stable equilibrium in which the two behaviours continue to segregate. A model in which the behaviours are determined by genes at two separate loci leads eventually to fixation of the alleles at both loci but this can take many generations of selection. Models of the type described in this paper will be needed to understand the evolution of complex behaviour when genomic or experimental information is available about the genetic determinants of behaviour and the selective values of different genomes. (c) 2007 Elsevier Inc. All rights reserved.
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Twenty first century challenges facing agriculture include climate change, threats to food security for a growing population and downward economic pressures on rural livelihoods. Addressing these challenges will require innovation in extension theory, policy and education, at a time when the dominance of the state in the provision of knowledge and information services to farmers and rural entrepreneurs continues to decline. This paper suggests that extension theory is catching up with and helping us to understand innovative extension practice, and therefore provides a platform for improving rural development policies and strategies. Innovation is now less likely to be spoken of as something to be passed on to farmers, than as a continuing process of creativity and adaptation that can be nurtured and sustained. Innovation systems and innovation platforms are concepts that recognise the multiple factors that lead to farmers’ developing, adapting and applying new ideas and the importance of linking all actors in the value chain to ensure producers can access appropriate information and advice for decision making at all stages in the production process. Concepts of social learning, group development and solidarity, social capital, collective action and empowerment all help to explain and therefore to apply more effectively group extension approaches in building confidence and sustaining innovation. A challenge facing educators is to ensure the curricula for aspiring extension professionals in our higher education institutions are regularly reviewed and keep up with current and future developments in theory, policy and practice.
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A simple self–contained theory is proposed for describing life cycles of convective systems as a discharge–recharge process. A closed description is derived for the dynamics of an ensemble of convective plumes based on an energy cycle. The system consists of prognostic equations for the cloud work function and the convective kinetic energy. The system can be closed by intro ducing a functional relationship between the convective kinetic energy and the cloud–base mass flux. The behaviour of this system is considered under a bulk simplification. Previous cloud–resolving mo delling as well as bulk statistical theories for ensemble convective systems suggest that a plausible relationship would be to assume that the convective kinetic energy is linearly proportional to the cloud–base mass flux. As a result, the system reduces to a nonlinear dynamical system with two dependent variables, the cloud–base mass flux and the cloud work function. The fully nonlinear solution of this system always represents a periodic cycle regardless of the initial condition under constant large–scale forcing. Importantly, the inclusion of energy dissipation in this model does not in itself lead the system to an equilibrium.
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In the current higher education climate, there is a growing perception that the pressures associated with being an academic middle manager outweigh the perceived rewards of the position. This article investigates the personal and professional circumstances that lead academics to become middle managers by drawing on data from life history interviews undertaken with 17 male and female department heads from a range of disciplines, in a post-1992 UK university. The data suggests that experiencing conflict between personal and professional identities, manifested through different socialization experiences over time, can lead to a ‘turning point’ and a decision that affects a person’s career trajectory. Although the results of this study cannot be generalized, the findings may help other individuals and institutions move towards a firmer understanding of the academic who becomes head of department—in relation to theory, practice and research.
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Background. In separate studies and research from different perspectives, five factors are found to be among those related to higher quality outcomes of student learning (academic achievement). Those factors are higher self-efficacy, deeper approaches to learning, higher quality teaching, students’ perceptions that their workload is appropriate, and greater learning motivation. University learning improvement strategies have been built on these research results. Aim. To investigate how students’ evoked prior experience, perceptions of their learning environment, and their approaches to learning collectively contribute to academic achievement. This is the first study to investigate motivation and self-efficacy in the same educational context as conceptions of learning, approaches to learning and perceptions of the learning environment. Sample. Undergraduate students (773) from the full range of disciplines were part of a group of over 2,300 students who volunteered to complete a survey of their learning experience. On completing their degrees 6 and 18 months later, their academic achievement was matched with their learning experience survey data. Method. A 77-item questionnaire was used to gather students’ self-report of their evoked prior experience (self-efficacy, learning motivation, and conceptions of learning), perceptions of learning context (teaching quality and appropriate workload), and approaches to learning (deep and surface). Academic achievement was measured using the English honours degree classification system. Analyses were conducted using correlational and multi-variable (structural equation modelling) methods. Results. The results from the correlation methods confirmed those found in numerous earlier studies. The results from the multi-variable analyses indicated that surface approach to learning was the strongest predictor of academic achievement, with self-efficacy and motivation also found to be directly related. In contrast to the correlation results, a deep approach to learning was not related to academic achievement, and teaching quality and conceptions of learning were only indirectly related to achievement. Conclusions. Research aimed at understanding how students experience their learning environment and how that experience relates to the quality of their learning needs to be conducted using a wider range of variables and more sophisticated analytical methods. In this study of one context, some of the relations found in earlier bivariate studies, and on which learning intervention strategies have been built, are not confirmed when more holistic teaching–learning contexts are analysed using multi-variable methods.