Trust,risk, and the social contract

The problem of trust is discussed in terms of David Hume’s meadow-draining example. This is analyzed in terms of rational choice, evolutionary game theory and a dynamic model of social network formation. The kind of explanation that postulates an innate predisposition to trust is seen to be unnecessary when social network dynamics is taken into account.     

Exchanges of group-based favours: Ingroup bias in the prisoner's dilemma game with minimal groups in Japan and New Zealand

Japanese ( N  = 48) and New Zealander ( N  = 55) participants were first assigned to one of two minimal groups, and then played a prisoner's dilemma game twice with an ingroup member and twice with an outgroup member. In one of the two games they played with an ingroup (or outgroup) member, participants and their partner knew one another's group memberships (mutual-knowledge condition). In the unilateral-knowledge condition, only the participants knew the group membership of their partner, but the partner did not know the group membership of the participant. Ingroup bias in cooperation emerged only in the mutual-knowledge condition in both countries; in the unilateral-knowledge condition no ingroup bias emerged. Mediational analyses found that, in accord with predictions, cooperation in the mutual-knowledge condition is mediated by expectation of the partner's cooperation. Ingroup bias in the mutual-knowledge condition emerged only among those who identified with the ingroup. Results provide support for a group heuristics account of ingroup favouritism in the minimal group. According to this account, participants who face minimal groups activate an ecologically adaptive heuristic of unilaterally cooperating with members of the same group, expecting indirect repayment from others in the same group.     

Combined reasoning by automated cooperation

Different reasoning systems have different strengths and weaknesses, and often it is useful to combine these systems to gain as much as possible from their strengths and retain as little as possible from their weaknesses. Of particular interest is the integration of first-order and higher-order techniques. First-order reasoning systems, on the one hand, have reached considerable strength in some niches, but in many areas of mathematics they still cannot reliably solve relatively simple problems, for example, when reasoning about sets, relations, or functions. Higher-order reasoning systems, on the other hand, can solve problems of this kind automatically. But the complexity inherent in their calculi prevents them from solving a whole range of problems. However, while many problems cannot be solved by any one system alone, they can be solved by a combination of these systems.We present a general agent-based methodology for integrating different reasoning systems. It provides a generic integration framework which facilitates the cooperation between diverse reasoners, but can also be refined to enable more efficient, specialist integrations. We empirically evaluate its usefulness, effectiveness and efficiency by case studies involving the integration of first-order and higher-order automated theorem provers, computer algebra systems, and model generators.     

Weakly higher order cylindric algebras and finite axiomatization of the representables

We show that the variety of n-dimensional weakly higher order cylindric algebras, introduced in Németi [9], [8], is finitely axiomatizable when n > 2. Our result implies that in certain non-well-founded set theories the finitization problem of algebraic logic admits a positive solution; and it shows that this variety is a good candidate for being the cylindric algebra theoretic counterpart of Tarski’s quasi-projective relation algebras. Supported by the Hungarian National Foundation for Scientific Research grant T73601.     

Do the right thing: but only if others do so

Social norms play an important role in individual decision making. We argue that two different expectations influence our choice to obey a norm: what we expect others to do (empirical expectations) and what we believe others think we ought to do (normative expectations). Little is known about the relative importance of these two types of expectation in individuals' decisions, an issue that is particularly important when normative and empirical expectations are in conflict (e.g., systemic corruption, high crime cities). In this paper, we report data from Dictator game experiments where we exogenously manipulate dictators' expectations in the direction of either selfishness or fairness. When normative and empirical expectations are in conflict, we find that empirical expectations about other dictators' choices significantly predict a dictator's own choice. However, dictators' expectations regarding what other dictators think ought to be done do not have a significant impact on their decisions after controlling for empirical expectations. Our findings about the crucial influence of empirical expectations are important for designing institutions or policies aimed at discouraging undesirable behavior. Copyright © 2008 John Wiley & Sons, Ltd.     

成败等因素对小学生游戏中自我价值感的影响

本研究以三、四年级的142名小学生为被试,以自编的"背投沙包"游戏为载体,通过创设竞争与合作的四类小组以及控制成功与失败的结果,探讨其对个体自我价值感的影响。研究发现,个体的自我价值感受到个体成败而非群体成败的影响,其中人际关系起着部分中介作用。尤其是在失败的结果产生后,极端的高能力重视水平能够带来高自我价值感。而竞争与合作的小组安排对自我价值感的影响并不显著。     

基于两方博弈关系分析的医保制度改进策略研究

刘璇张朋柱张敏针对医保制度实施以来的实际运作情况,从博弈角度分析了医保基金缴纳和使用异常行为出现的原因;并从改变博弈均衡解的角度提出了有效引导企业、医患、医院走出异常的一系列措施建立针对企业、医患、医院的黑名单制度,通过信息共享降低监督成本,将服务质量纳入与医院的结算办法等。     

The Hennessy–Milner equivalence for continuous time stochastic logic with mu-operator

A continuous stochastic logic with a μ-operator μCSL is defined, and an interpretation through stochastic relations is proposed. We investigate morphisms for models of μCSL, showing that the associated congruences can be used for an investigation of bisimilarity. The Hennessy–Milner equivalence for μCSL is discussed, and it is shown that models are equivalent iff they are bisimilar, using a general criterion for bisimilarity from the theory of stochastic relations.     

暴力视频游戏中不同攻击动机对玩家攻击性的影响

分别采用词汇按键反应任务和EAST范式测查了攻击性认知的流畅性和内隐攻击性评价,旨在考察游戏中攻击动机对攻击性的影响,结果发现：暴力视频游戏的影响效应不仅与暴力内容有关,还受制于攻击动机和玩家的暴力游戏经验;且长期玩暴力游戏会使被试对暴力产生脱敏,表现为攻击性认知的流畅性低,对攻击的评价更积极。本研究表明,暴力视频游戏对个体攻击性的影响需综合考虑多种因素。