Clan information market games

We introduce a TU-game that describes a market where information is distributed among several agents and all these pieces of information are necessary to produce a good. This situation will be called clan information market. The class of the corresponding TU-games, the clan information market games (CIGs), is a subset of the class of clan games. We provide some well-known point solutions for CIGs in terms of the market data.     

A Banzhaf share function for cooperative games in coalition structure

A cooperative game with transferable utility–or simply a TU-game– describes a situation in which players can obtain certain payoffs by cooperation. A value function for these games assigns to every TU-game a distribution of payoffs over the players. Well-known solutions for TU-games are the Shapley and the Banzhaf value. An alternative type of solution is the concept of share function, which assigns to every player in a TU-game its share in the worth of the grand coalition. In this paper we consider TU-games in which the players are organized into a coalition structure being a finite partition of the set of players. The Shapley value has been generalized by Owen to TU-games in coalition structure. We redefine this value function as a share function and show that this solution satisfies the multiplication property that the share of a player in some coalition is equal to the product of the Shapley share of the coalition in a game between the coalitions and the Shapley share of the player in a game between the players within the coalition. Analogously we introduce a Banzhaf coalition structure share function. Application of these share functions to simple majority games show some appealing properties.     

Two-Person and majority continuous aggregation in 2-good space in Social Choice: a note

Impossibility theorems for 2-person and majority continuous games on the unit circle are presented. The emphasis is on simple methods, albeit generating new results, to offer insights into the sophisticated results of theorists in topological social choice.     

The Lovász Extension of Market Games

The multilinear extension of a cooperative game was introduced by Owen in 1972. In this contribution we study the Lovász extension for cooperative games by using the marginal worth vectors and the dividends. First, we prove a formula for the marginal worth vectors with respect to compatible orderings. Next, we consider the direct market generated by a game. This model of utility function, proposed by Shapley and Shubik in 1969, is the concave biconjugate extension of the game. Then we obtain the following characterization: The utility function of a market game is the Lovász extension of the game if and only if the market game is supermodular. Finally, we present some preliminary problems about the relationship between cooperative games and combinatorial optimization.     

A Short-term Longitudinal Study of Children's Playground Games in Primary School: Implications for Adjustment to School and Social Adjustment in the USA and the UK

In this study we described development of boys’ and girls’ games on the school playground at recess as they progressed across the first year of primary school in London (UK) and Minneapolis (USA) in order to document age‐related trends in games during this period and to examine the predictive role of games in children's adjustment to school and more general social adjustment. Consistent with expectations, games accounted for a significant portion of children’s, but especially boys’, behavior during recess. American children played games more frequently, especially simple games, relative to English children. Consistent with expectation, the complexity of games increased, especially for boys, across the school year for children in both countries. We also examined the extent to which facility with games forecasted adjustment to school and social adjustment. Games predicted both, but only in the USA sample. Results are discussed in terms of games being an important developmental task for children of this age. Implications for future research and educational policy are discussed.     

Regular updating

This article presents a new model aimed at predicting behavior in games involving a randomized allocation procedure. It is designed to capture the relative importance and interaction between procedural justice (defined crudely in terms of the difference between one’s expected payoff and average expected payoff in the group) and distributive justice (difference between own and average actual payoffs). The model is applied to experimental games, including “randomized” variations of simple sequential bargaining games, and delivers qualitatively correct predictions. In view of the model redistribution of income can be seen as a substitute for vertical social mobility. This contributes to the explanation of greater demand for redistribution in European countries vis-a-vis the United States. I conclude with suggestions for further verification of the model and possible extensions.     

Arbitrage,rationality, and equilibrium

No-arbitrage is the fundamental principle of economic rationality which unifies normative decision theory, game theory, and market theory. In economic environments where money is available as a medium of measurement and exchange, no-arbitrage is synonymous with subjective expected utility maximization in personal decisions, competitive equilibria in capital markets and exchange economies, and correlated equilibria in noncooperative games. The arbitrage principle directly characterizes rationality at the market level; the appearance of deliberate optimization by individual agents is a consequence of their adaptation to the market. Concepts of equilibrium behavior in games and markets can thus be reconciled with the ideas that individual rationality is bounded, that agents use evolutionarily-shaped decision rules rather than numerical optimization algorithms, and that personal probabilities and utilities are inseparable and to some extent indeterminate. Risk-neutral probability distributions, interpretable as products of probabilities and marginal utilities, play a central role as observable quantities in economic systems.     

On the consistency of choice

Consistency of choice is a fundamental and recurring theme in decision theory, social choice theory, behavioral economics, and psychological sciences. The purpose of this paper is to study the consistency of choice independent of the particular decision model at hand. Consistency is viewed as an inherently logical concept that is fundamentally void of connotation and is thus disentangled from traditional rationality or consistency conditions imposed on decision models. The proposed formalization of consistency takes two forms: internal consistency, which refers to the property that a choice model does not generate contradictory statements; and semantic consistency, which refers to the idea that a theory’s predictions are valid with respect to some observed data. In addressing semantic consistency, the relationship between theory and data is analyzed in terms of so-called duality mappings, which allow a passage between the two universes in a way that consistency is preserved. The formalization of consistency concepts relies on adapting the revealed preference theory to the context-dependent setting. The paper concludes by discussing the implications of the proposed framework and how it relates to classical revealed preference theory and other formalizations of the relationship between the theory and reality of choice.     

Adolescents with an entity theory of personality are more vigilant to social status and use relational aggression to maintain social status

The present research proposed that one social‐cognitive root of adolescents' willingness to use relational aggression to maintain social status in high school is an entity theory of personality, which is the belief that people's social status‐relevant traits are fixed and cannot change. Aggregated data from three studies (N = 882) showed that first‐year high school adolescents in the United States who endorsed more of an entity theory were more likely to show cognitive and motivational vigilance to social status, in terms of judgments on a novel social categorization task and reports of goals related to demonstrating social status to peers. Those with an entity theory then showed a greater willingness to use relational aggression, as measured by retrospective self‐reports, responses to a hypothetical scenario, and a choice task. Discussion centers on theoretical and translational implications of the model and of the novel measures.     

结合案例分析游戏在儿童社会工作个案辅导中的运用

游戏是儿童表达想法和感受的重要媒介,在儿童的成长生活中占据着非常重要的地位。社会工作实务辅导有必要重视游戏对儿童的意义,将之融合进实务辅导之中。但目前我国社会工作专业领域中尚缺乏相关的理论和实践经验。本文结合自身实务经验,提出专业社工可在三个层面借鉴西方儿童游戏治疗理论的经验,指导个案辅导中的游戏运用,以期可以促进儿童个案社会工作实务的新发展。     

结合案例分析游戏在儿童社会工作个案辅导中的运用

游戏是儿童表达想法和感受的重要媒介,在儿童的成长生活中占据着非常重要的地位。社会工作实务辅导有必要重视游戏对儿童的意义,将之融合进实务辅导之中。但目前我国社会工作专业领域中尚缺乏相关的理论和实践经验。本文结合自身实务经验,提出专业社工可在三个层面借鉴西方儿童游戏治疗理论的经验,指导个案辅导中的游戏运用,以期可以促进儿童个案社会工作实务的新发展。     

An incompleteness problem in Harsanyi's general theory of games and certain related theories of non-cooperative games

The theory of games recently proposed by John C. Harsanyi in A General Theory of Rational Behavior in Game Situations, (Econometrica, Vol. 34, No. 3) has one anomalous feature, viz., that it generates for a special class of non-cooperative games solutions which are not equilibrium points. It is argued that this feature of the theory turns on an argument concerning the instability of weak equilibrium points, and that this argument, in turn, involves appeal to an unrestricted version of a postulate subsequently included in the theory in restricted form. It is then shown that if this line of reasoning is permitted, then one must, by parity of reasoning, permit another instability argument. But, if both of these instability arguments are permitted in the construction of the theory, the resultant theory must be incomplete, in the sense that there will be simple non-cooperative games for which such a theory cannot yield solutions. This result is then generalized and shown to be endemic to all theories which have made the equilibrium condition central to the treatment of non-cooperative games. Some suggestions are then offered concerning how this incompleteness problem can be resolved, and what one might expect concerning the postulate structure and implications of a theory of games which embodies the revisions necessitated by a resolution of this problem.This research was supported by a grant to the author from the City University of New York Faculty Research Award Program.     

An application of social choice theory to U.S.D.A. forest service decision making

To meet the requirements of the National Environmental Policy Act of 1969, the U.S.D.A. Forest Service has changed the way forest plans are developed. The focus of this paper is to address the group-decision problem using social choice theory, specifically the voting models of Condorcet and Borda. The elements of a social choice problem are voters, alternatives, preferences, and aggregation. A case study from the Shoshone National Forest is used to demonstrate the use of the voting models from social choice theory. The solutions derived from the analysis are strategy and coalitional strategy proof implying that behaviors intended to influence the outcome, such as vote trading, would be unsuccessful.     

A choice for ‘me’ or for ‘us’? Using we-reasoning to predict cooperation and coordination in games

Cooperation is the foundation of human social life, but it sometimes requires individuals to choose against their individual self-interest. How then is cooperation sustained? How do we decide when instead to follow our own goals? I develop a model that builds on Bacharach (in: Gold, Sugden (eds) Beyond individual choice: teams and frames in game theory, 2006) ??circumspect we-reasoning?? to address these questions. The model produces a threshold cost/benefit ratio to describe when we-reasoning players should choose cooperatively. After assumptions regarding player types and beliefs, we predict how the extent of cooperation varies across games. Results from two experiments offer strong support to the models and predictions herein.     

北京后奥运时代我国体育改革的路径选择

本文提出北京后奥运时代我国体育改革的路径,自上而下的政府主导的强制性体育体制改革与自下而上的社会选择的引导性体育体制改革相结合、整体的渐进性体育体制改革和局部的激进性体育体制改革相结合的方式。     

Do-It-Yourself Social Policy: Searching for a New Paradigm?

One of the most significant trends of recent decades has been the growing importance of do-it-yourself social policy: i.e. individuals constructing their own welfare mix both within the public sector and in private markets. This paper argues that this challenges the traditional top-down bias of social policy studies and requires a shift of focus within the discipline. The implications for normative theory, research strategy and policy analysis are explored. Some of the arguments for and against choice as a guiding principle are sketched out; some existing research on benefit take-up and choice in education and health is reviewed and the case for moving away from the economist's simple model of rationality is put forward. Finally, we argue, there should be more emphasis in social policy on developing a better understanding of the way in which individuals take their decisions, the context of public policy within which they act and the interaction between the two.     

Towards the Use and Development of Games for Social Work Practice

Summary This paper reviews games that may be of use to social workersin their work with individuals, couples, families and groups.A typology of games is presented, which categorizes games accordingto their structure and their function. Games are seen as eitherunstructured or structured, and as stressing either cognitiveor behavioural goals. Selected games are presented in more detailas examples and others are presented in brief in an annotatedbibliography. Issues relating to designing games are discussedas well as issues in applying games to social work practice.     

An axiomatic analysis of the Nash equilibrium concept

The purpose of this paper is to analyze axiomatically the Nash equilibrium concept. The class of games under study is a (relatively large) subclass of n-person normal form games. Solutions are correspondences which associate to each game a non empty set of strategy vectors of this game. It is shown that if a solution satisfies the axioms Independence of irrelevant alternatives (IIA) and Individual rationality (IR), then all the strategy vectors in this solution are Nash equilibria. This result holds good also if IR is replaced by Strong individual monotonicity (SIM) or Weak principle of fair compromise (WPFC).     

The <Emphasis Type="Italic">γ</Emphasis>-core in Cournot oligopoly TU-games with capacity constraints

In cooperative Cournot oligopoly games, it is known that the β-core is equal to the α-core, and both are non-empty if every individual profit function is continuous and concave (Zhao, Games Econ Behav 27:153–168, 1999b). Following Chander and Tulkens (Int J Game Theory 26:379–401, 1997), we assume that firms react to a deviating coalition by choosing individual best reply strategies. We deal with the problem of the non-emptiness of the induced core, the γ-core, by two different approaches. The first establishes that the associated Cournot oligopoly Transferable Utility (TU)-games are balanced if the inverse demand function is differentiable and every individual profit function is continuous and concave on the set of strategy profiles, which is a step forward beyond Zhao’s core existence result for this class of games. The second approach, restricted to the class of Cournot oligopoly TU-games with linear cost functions, provides a single-valued allocation rule in the γ-core called Nash Pro rata (NP)-value. This result generalizes Funaki and Yamato’s (Int J Game Theory 28:157–171, 1999) core existence result from no capacity constraint to asymmetric capacity constraints. Moreover, we provide an axiomatic characterization of this solution by means of four properties: efficiency, null firm, monotonicity, and non-cooperative fairness.