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Folk Theorem (game Theory)
In game theory, folk theorems are a class of theorems describing an abundance of Nash equilibrium payoff profiles in repeated games . The original Folk Theorem concerned the payoffs of all the Nash equilibria of an infinitely repeated game. This result was called the Folk Theorem because it was widely known among game theorists in the 1950s, even though no one had published it. Friedman's (1971) Theorem concerns the payoffs of certain subgame-perfect Nash equilibria (SPE) of an infinitely repeated game, and so strengthens the original Folk Theorem by using a stronger equilibrium concept: subgame-perfect Nash equilibria rather than Nash equilibria. The Folk Theorem suggests that if the players are patient enough and far-sighted (i.e. if the discount factor \delta \to 1 ), then repeated interaction can result in virtually any average payoff in an SPE equilibrium. "Virtually any" is here technically defined as "feasible" and "individually rational". Setup and definitions We sta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Game Theory
Game theory is the study of mathematical models of strategic interactions. It has applications in many fields of social science, and is used extensively in economics, logic, systems science and computer science. Initially, game theory addressed two-person zero-sum games, in which a participant's gains or losses are exactly balanced by the losses and gains of the other participant. In the 1950s, it was extended to the study of non zero-sum games, and was eventually applied to a wide range of Human behavior, behavioral relations. It is now an umbrella term for the science of rational Decision-making, decision making in humans, animals, and computers. Modern game theory began with the idea of mixed-strategy equilibria in two-person zero-sum games and its proof by John von Neumann. Von Neumann's original proof used the Brouwer fixed-point theorem on continuous mappings into compact convex sets, which became a standard method in game theory and mathematical economics. His paper was f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Overtaking Criterion
In economics, the overtaking criterion is used to compare infinite streams of outcomes. Mathematically, it is used to properly define a notion of optimality for a problem of optimal control on an unbounded time interval. Often, the decisions of a policy-maker may have influences that extend to the far future. Economic decisions made today may influence the economic growth of a nation for an unknown number of years into the future. In such cases, it is often convenient to model the future outcomes as an infinite stream. Then, it may be required to compare two infinite streams and decide which one of them is better (for example, in order to decide on a policy). The overtaking criterion is one option to do this comparison. Notation X is the set of possible outcomes. E.g., it may be the set of positive real numbers, representing the possible annual gross domestic product. It is normalized X^\infty is the set of infinite sequences of possible outcomes. Each element in X^\infty is of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Program Equilibrium
Program equilibrium is a game theory , game-theoretic solution concept for a scenario in which players submit computer programs to play the game on their behalf and the programs can read each other's source code. The term was introduced by Moshe Tennenholtz in 2004. The same setting had previously been studied by R. Preston McAfee, J. V. Howard and Ariel Rubinstein. Setting and definition The program equilibrium literature considers the following setting. Consider a normal-form game as a base game. For simplicity, consider a two-player game in which S_1 and S_2 are the sets of available strategy (game theory) , strategies and u_1 and u_2 are the players' Utility#Functions , utility functions. Then we construct a new (normal-form) ''program game'' in which each player i chooses a computer program p_i. The payoff (utility) for the players is then determined as follows. Each player's program p_i is run with the other program p_ as input and outputs a strategy s_i for Player i. F ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Moshe Tennenholtz
Moshe Tennenholtz (Hebrew: משה טננהולץ) is an Israeli computer scientist and professor with the faculty of Data and Decision Sciences at the Technion – Israel Institute of Technology, where he holds the Sondheimer Technion Academic Chair. Biography Tennenholtz received his B.Sc. in mathematics from Tel Aviv University in 1986, and his M.Sc. and Ph.D. in 1987 and 1991 respectively from the Department of Applied Mathematics and Computer Science in the Weizmann Institute. From 1991 to 1993 he worked in the Robotics Laboratory at Stanford University, after which he joined the faculty at the Technion in Haifa. He returned to Stanford briefly as a visiting professor from 1999 to 2002 before returning to the Technion. In 2008 he started working at Microsoft Research and in 2011 he founded the basic research group at the Microsoft Israel R&D center. He has served as editor-in-chief of the ''Journal of Artificial Intelligence Research'', associate editor of ''Games and Economic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Overtaking
Overtaking or passing is the act of one vehicle going past another slower moving vehicle, travelling in the same direction, on a road. The lane used for overtaking another vehicle is often a passing lane farther from the road shoulder, which is to the left in places that drive on the right and to the right in places that drive on the left. Rules of overtaking In English-speaking countries On a single carriageway, single-carriageway/undivided-highway road, the lane used for overtaking is often the same lane that is used by oncoming traffic. An overtaking vehicle must be able to see clearly ahead of them for the entire overtaking manoeuvre plus a margin of error. For example, in New Zealand it's instructed in the Road Code that an overtaking driver must be able to see at least of clear road in front of them as they finish the passing manoeuvre. In the UK, guidance for passing and overtaking is given in rules 162-169 of the Highway Code. In some jurisdictions, the "overtaking ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PPAD (complexity)
In computer science, PPAD ("Polynomial Parity Arguments on Directed graphs") is a complexity class introduced by Christos Papadimitriou in 1994. PPAD is a subclass of TFNP based on functions that can be shown to be total by a parity argument. The class attracted significant attention in the field of algorithmic game theory because it contains the problem of computing a Nash equilibrium: this problem was shown to be complete for PPAD by Daskalakis, Goldberg and Papadimitriou with at least 3 players and later extended by Chen and Deng to 2 players.*. Definition PPAD is a subset of the class TFNP, the class of function problems in FNP that are guaranteed to be total. The TFNP formal definition is given as follows: :A binary relation P(''x'',''y'') is in TFNP if and only if there is a deterministic polynomial time algorithm that can determine whether P(''x'',''y'') holds given both ''x'' and ''y'', and for every ''x'', there exists a ''y'' such that P(''x'',''y'') holds. Subclasses ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oligopoly
An oligopoly () is a market in which pricing control lies in the hands of a few sellers. As a result of their significant market power, firms in oligopolistic markets can influence prices through manipulating the supply function. Firms in an oligopoly are mutually interdependent, as any action by one firm is expected to affect other firms in the market and evoke a reaction or consequential action. As a result, firms in oligopolistic markets often resort to collusion as means of maximising profits. Nonetheless, in the presence of fierce competition among market participants, oligopolies may develop without collusion. This is a situation similar to perfect competition, where oligopolists have their own market structure. In this situation, each company in the oligopoly has a large share in the industry and plays a pivotal, unique role. Many jurisdictions deem collusion to be illegal as it violates competition laws and is regarded as anti-competition behaviour. The EU com ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Franklin Fisher
Franklin Marvin Fisher (December 13, 1934 – April 29, 2019) was an American economist. He taught economics at the Massachusetts Institute of Technology from 1960 to 2004. Biography Fisher attended Harvard University, where he was inducted into Phi Beta Kappa in 1955 and received a Bachelor of Arts degree (''summa cum laude'') in 1956, followed by a Master's degree in 1957 and a Ph.D. in Economics from Harvard in 1960. His doctoral thesis was entitled ''A Priori Information and Time Series Analysis''. Fisher married Ellen Paradise Fisher in 1958. They had three children and eight grandchildren. He was Teaching Fellow at Harvard from 1956 to 1957, Junior Fellow of the Society of Fellows at Harvard (1957–59), Assistant Professor of Economics at the University of Chicago (1959–60), Assistant Professor of Economics at MIT (1960–62), Associate Professor of Economics at MIT (1962–65), and Professor of Economics at MIT from 1965 to 2004. He retired as the Jane Berkowitz Car ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Social Norm
A social norm is a shared standard of acceptance, acceptable behavior by a group. Social norms can both be informal understandings that govern the behavior of members of a society, as well as be codified into wikt:rule, rules and laws. Social normative influences or social norms, are deemed to be powerful drivers of human behavioural changes and well organized and incorporated by major theories which explain human behaviour. Institutions are composed of multiple norms. Norms are shared social beliefs about behavior; thus, they are distinct from "ideas", "attitudes", and "values", which can be held privately, and which do not necessarily concern behavior. Norms are contingent on context, social group, and historical circumstances. Scholars distinguish between regulative norms (which constrain behavior), constitutive norms (which shape interests), and prescriptive norms (which prescribe what actors ''ought'' to do). The effects of norms can be determined by a logic of appropriateness ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taboo
A taboo is a social group's ban, prohibition or avoidance of something (usually an utterance or behavior) based on the group's sense that it is excessively repulsive, offensive, sacred or allowed only for certain people.''Encyclopædia Britannica Online''.Taboo. Encyclopædia Britannica Inc., 2012. Retrieved 21 Mar. 2012 Such prohibitions are present in virtually all societies. Taboos may be prohibited explicitly, for example within a legal system or religion, or implicitly, for example by social norms or conventions followed by a particular culture or organization. Taboos are often meant to protect the individual, but there are other reasons for their development. An ecological or medical background is apparent in many, including some that are seen as religious or spiritual in origin. Taboos can help use a resource more efficiently, but when applied to only a subsection of the community they can also serve to suppress said subsection of the community. A taboo acknowledged by a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tradition
A tradition is a system of beliefs or behaviors (folk custom) passed down within a group of people or society with symbolic meaning or special significance with origins in the past. A component of cultural expressions and folklore, common examples include holidays or impractical but socially meaningful clothes (like lawyers' wigs or military officers' spurs), but the idea has also been applied to social norms and behaviors such as greetings, etc. Traditions can persist and evolve for thousands of years— the word ''tradition'' itself derives from the Latin word ''tradere'' literally meaning to transmit, to hand over, to give for safekeeping. While it is reportedly assumed that traditions have an ancient history, many traditions have been invented on purpose, whether it be political or cultural, over short periods of time. Various academic disciplines also use the word in a variety of ways. The phrase "according to tradition" or "by tradition" usually means that what ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anthropology
Anthropology is the scientific study of humanity, concerned with human behavior, human biology, cultures, society, societies, and linguistics, in both the present and past, including archaic humans. Social anthropology studies patterns of behaviour, while cultural anthropology studies cultural meaning, including norms and values. The term sociocultural anthropology is commonly used today. Linguistic anthropology studies how language influences social life. Biological anthropology, Biological (or physical) anthropology studies the biology and evolution of Human evolution, humans and their close primate relatives. Archaeology, often referred to as the "anthropology of the past," explores human activity by examining physical remains. In North America and Asia, it is generally regarded as a branch of anthropology, whereas in Europe, it is considered either an independent discipline or classified under related fields like history and palaeontology. Etymology The abstract noun ''wikt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
