Acting for reasons: Reply to Dancy

This paper argues that we need to distinguish between two different ideas of a reason: first, the idea of a premise or assumption, from which a person’s action or deliberation can proceed; second, the idea of a fact by which a person can be guided, when he modifies his thought or behaviour in some way. It argues further that if we have the first idea in mind, one can act for the reason that p regardless of whether it is the case that p, and regardless of whether one believes that p. But if we have the second idea in mind, one cannot act for the reason that p unless one knows that p. The last part of the paper briefly indicates how the second idea of a reason can contribute to a larger argument, showing that it is better to conceive of knowledge as a kind of ability than as a kind of belief.     

观念运动理论：内涵与证据

人类日常动作有两种类型, 一是是对外界刺激的反应, 是一种自下而上的动作模式, 即感觉运动(sensorimotor)模式; 二是以人们头脑中的观念意图为基础, 由观念引导, 为了实现一个特定的目标而执行特定的动作, 是一种自上而下的动作模式, 即观念运动(ideomotor)模式。观念运动理论(ideomotor theory)所解释的就是以基于意图的动作。该理论经历了长期的演变, 一般动作执行与动作模仿领域内的行为与神经科学研究的证据初步证实了观念运动的理论构想与主要机制：共同编码机制与镜像神经机制。观念运动理论在贯通感知觉与动作方面具有重大意义, 由此还产生了共享环路模型(shared circuits model, SCM)等新近观点。此外, 观念运动理论还强调了目标和预期的重要地位。未来还需加强对动作与意图之间的通路, 以及动作的本体性效果等方面的研究。     

On the equivalence between elimination-by-aspects and generalised extreme value models of choice behaviour

Elimination-by-aspects and generalised extreme value offer competing paradigms for the representation of a common behaviour, that of individual discrete choice. Observing certain consistencies in their mathematical structure, several eminent authors have commented on the degree of equivalence between the two paradigms. Most contributions to this debate have, however, been less than definitive. More fundamentally, the contributions lack consensus. We advance the debate by establishing formal mathematical conditions under which three-alternative tree models from the two paradigms are exactly equivalent. We then extend our analysis to consider more general models, showing that equivalence can be established for general tree models, but not for cross-nested models.     

Satir Model of Family Therapy and Spiritual Direction

To consider a connection between the therapy model named under Virginia Satir and the practice of spiritual direction may arouse suspicion. This paper, however, attempts to show that the link between the two is natural, sensible, and inspiring, particularly for the part of spiritual direction. The first section of the paper first addresses the fact that spiritual direction, with its unique focus, is not to be confused with psychotherapy, then, discusses the recognized need to seek a psychologically sound model of spiritual direction. The second section describes some of the useful concepts in the Satir model and then relates them to the various aspects of spiritual direction. It is believed that the Satir model of therapy can enrich the practice of spiritual direction in a number of ways. Ekman P. C. Tam is the Spiritual Director of Tao Fong Shan Christian Centre, Hong Kong.     

Optimal Partitioning of Testing Time: Theoretical Properties and Practical Implications

This paper deals with optimal partitioning of limited testing time in order to achieve maximum total test score. Nonlinear optimization theory was used to analyze this problem. A general case using a generic item response model is first presented. A special case that applies a response time model proposed by Wang and Hanson (2005) is also presented. Theoretical properties of the optimal solution are derived. Their practical implications to optimal test-taking strategies are also discussed. The theoretical properties are in general agreement with the conventional advice to the examinees on pacing strategy.     

An Impossibility Theorem on Beliefs in Games

A paradox of self-reference in beliefs in games is identified, which yields a game-theoretic impossibility theorem akin to Russell’s Paradox. An informal version of the paradox is that the following configuration of beliefs is impossible:Ann believes that Bob assumes thatAnn believes that Bob’s assumption is wrongThis is formalized to show that any belief model of a certain kind must have a ‘hole.’ An interpretation of the result is that if the analyst’s tools are available to the players in a game, then there are statements that the players can think about but cannot assume. Connections are made to some questions in the foundations of game theory.Special Issue Ways of Worlds II. On Possible Worlds and Related Notions Edited by Vincent F. Hendricks and Stig Andur Pedersen     

Mechanisms for enhancing the credibility of an adviser: prepayment and aligned incentives

We tested the effectiveness of prepayment for advice and aligned incentives as mechanisms for enhancing trust in unfamiliar advisers in decision‐making under uncertainty. Participants were low‐income Zimbabweans who played two rounds of the Monty Hall three‐door game. In round 1, participants who purchased advice were significantly more likely to follow advice for how to win the game than were participants who received free advice. In round 2, the apparent effectiveness of advisers' suggestions in round 1 moderated participants' propensity to follow advice. If the round 1 advice appeared wrong, the credibility enhancing benefits of prepayment diminished. If the advice appeared right, the benefits of prepayment maintained. Hypotheses with regard to the benefits of aligned incentives received only weak support. Copyright © 2006 John Wiley & Sons, Ltd.