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Généralisé aux enchères au second prix - Wikipedia, l'encyclopédie libre. The generalized second-price auction (GSP) is a non-truthful auction mechanism for multiple items.

Généralisé aux enchères au second prix - Wikipedia, l'encyclopédie libre

Each bidder places a bid. The highest bidder gets the first slot, the second-highest, the second slot and so on, but the highest bidder pays the price bid by the second-highest bidder, the second-highest pays the price bid by the third-highest, and so on. First conceived as a natural extension of the Vickrey auction, it in fact does conserve some of the good properties of the Vickrey auction. It is used mainly in the context of keyword auctions, where sponsored search slots are sold on an auction basis. The first analyses of GSP are in the economics literature by Edelman, Ostrovsky, and Schwarz[1] and by Varian.[2] It is employed by Google's AdWords technology. Formal model[edit] Consider there are bidders and slots. . We can think of. Routage - Wikipedia, l'encyclopédie libre. Routing is the process of selecting best paths in a network.

Routage - Wikipedia, l'encyclopédie libre

In the past, the term routing was also used to mean forwarding network traffic among networks. However this latter function is much better described as simply forwarding. Routing is performed for many kinds of networks, including the telephone network (circuit switching), electronic data networks (such as the Internet), and transportation networks. This article is concerned primarily with routing in electronic data networks using packet switching technology. In case of overlapping/equal routes, the following elements are considered in order to decide which routes get installed into the routing table (sorted by priority): Delivery semantics[edit] Routing schemes differ in their delivery semantics: Unicast is the dominant form of message delivery on the Internet. Behavioral experiments on biased voting in networks. Author Affiliations Edited by Ronald L.

Behavioral experiments on biased voting in networks

Graham, University of California at San Diego, La Jolla, CA, and approved December 5, 2008 (received for review August 19, 2008) Abstract Many distributed collective decision-making processes must balance diverse individual preferences with a desire for collective unity. Behavioral dynamics and influence in networked coloring and consensus. Author Affiliations Edited by Brian Skyrms, University of California, Irvine, CA, and approved July 16, 2010 (received for review February 3, 2010) A correction has been published Abstract We report on human-subject experiments on the problems of coloring (a social differentiation task) and consensus (a social agreement task) in a networked setting.

Behavioral dynamics and influence in networked coloring and consensus

Game theory. Game theory is the study of strategic decision making.

Game theory

Specifically, it is "the study of mathematical models of conflict and cooperation between intelligent rational decision-makers. "[1] An alternative term suggested "as a more descriptive name for the discipline" is interactive decision theory.[2] Game theory is mainly used in economics, political science, and psychology, as well as logic, computer science, and biology. The subject first addressed zero-sum games, such that one person's gains exactly equal net losses of the other participant or participants. Today, however, game theory applies to a wide range of behavioral relations, and has developed into an umbrella term for the logical side of decision science, including both humans and non-humans (e.g. computers, animals). Modern game theory began with the idea regarding the existence of mixed-strategy equilibria in two-person zero-sum games and its proof by John von Neumann. Expérience petit monde - Wikipedia, l'encyclopédie libre.

The "six degrees of separation" model The small-world experiment comprised several experiments conducted by Stanley Milgram and other researchers examining the average path length for social networks of people in the United States.

Expérience petit monde - Wikipedia, l'encyclopédie libre

The research was groundbreaking in that it suggested that human society is a small-world-type network characterized by short path-lengths. The experiments are often associated with the phrase "six degrees of separation", although Milgram did not use this term himself. Historical context of the small-world problem[edit] Mathematician Manfred Kochen and political scientist Ithiel de Sola Pool wrote a mathematical manuscript, "Contacts and Influences", while working at the University of Paris in the early 1950s, during a time when Milgram visited and collaborated in their research.

Milgram's experiment was conceived in an era when a number of independent threads were converging on the idea that the world is becoming increasingly interconnected. Théorie des graphes. Un article de Wikipédia, l'encyclopédie libre.

Théorie des graphes

La théorie des graphes est une théorie informatique et mathématique. Équilibre de Nash - Wikipedia, l'encyclopédie libre. In game theory, the Nash equilibrium is a solution concept of a non-cooperative game involving two or more players, in which each player is assumed to know the equilibrium strategies of the other players, and no player has anything to gain by changing only their own strategy.[1] If each player has chosen a strategy and no player can benefit by changing strategies while the other players keep theirs unchanged, then the current set of strategy choices and the corresponding payoffs constitutes a Nash equilibrium.

Équilibre de Nash - Wikipedia, l'encyclopédie libre

The reality of the Nash equilibrium of a game can be tested using experimental economics method. Stated simply, Amy and Will are in Nash equilibrium if Amy is making the best decision she can, taking into account Will's decision while Will's decision remains unchanged, and Will is making the best decision he can, taking into account Amy's decision while Amy's decision remains unchanged. Applications[edit] History[edit] The Nash equilibrium was named after John Forbes Nash, Jr. Let . Erdös Numéro du projet - Le projet Nombre Erdös - Université d'Oakland. Un algorithme pour mettre en rang une équipe de football. Réaliser un alignement, une évidence ?

Un algorithme pour mettre en rang une équipe de football

Pas si sûr... Du sport de ballon au sport cérébral, découvrez différentes méthodes pour y parvenir. 1. Aligner des joueurs sur un terrain Lors de la dernière coupe du monde de football, l’équipe d’Allemagne a chuté en demi-finale mais a impressionné par sa qualité de jeu et par sa rigueur. Tous les joueurs sont sur le terrain, en train de s'échauffer, et peuvent se déplacer sur toute la surface. Les joueurs doivent se placer entre les deux drapeaux, pour former une ligne, et se positionner à intervalles réguliers.

La méthode allemande Au départ, les joueurs sont éparpillés sur le terrain. Le sélectionneur agit du bord du terrain. Au bout de plusieurs itérations, les joueurs forment plus ou moins un rang. Chaque itération prend un peu de temps, car chaque joueur i attend que le joueur (i-1) ait bougé pour se déplacer à son tour. Tout le monde sait que l'équipe de France n'a pas brillé à la coupe du monde. La méthode espagnole La méthode du XV de France. Introduction à la logique mathématique.