Environments That Make Us Smart: Ecological Rationality

ABSTRACT— Traditional views of rationality posit general-purpose decision mechanisms based on logic or optimization. The study of ecological rationality focuses on uncovering the "adaptive toolbox" of domain-specific simple heuristics that real, computationally bounded minds employ, and explaining how these heuristics produce accurate decisions by exploiting the structures of information in the environments in which they are applied. Knowing when and how people use particular heuristics can facilitate the shaping of environments to engender better decisions.     

Quantifiers and Congruence Closure

We prove some results about the limitations of the expressive power of quantifiers on finite structures. We define the concept of a bounded quantifier and prove that every relativizing quantifier which is bounded is already first-order definable (Theorem 3.8). We weaken the concept of congruence closed (see [6]) to weakly congruence closed by restricting to congruence relations where all classes have the same size. Adapting the concept of a thin quantifier (Caicedo [1]) to the framework of finite structures, we define the concept of a meager quantifier. We show that no proper extension of first-order logic by means of meager quantifiers is weakly congruence closed (Theorem 4.9). We prove the failure of the full congruence closure property for logics which extend first-order logic by means of meager quantifiers, arbitrary monadic quantifiers, and the Härtig quantifier (Theorem 6.1).     

有限理性信任观:对理性计算和非理性态度的整合

信任是理性的还是非理性的,一直是信任研究中争论的焦点。在对理性信任观和非理性信任观进行比较分析之后,在"有限理性"和"心智成本"的框架下,提出了信任的有限理性观点,对信任的理性观和非理性观点做一整合。     

最优化与满意型决策风格孰优孰劣?

最优化决策者追求决策的最优解,满意型决策者寻求决策的满意解.已有研究以理性模型和有限理性模型为基础,提出了两类决策风格的概念并且从两类决策者的决策特征和心理指标这两个角度详细对比了两类决策风格的差异.就纯粹的经济学效益、主观的心理学意义和现实的决策选择这三方面而言,“两类决策风格孰优孰劣”是一个因人而异,因决策目标而异的问题.未来研究可以在清晰界定两类决策风格概念的基础上进一步完善测量工具,从而深入探讨两类决策风格的领域特异性、与正性情绪的关系及其心理悖论的根源.     

Expressivity of Second Order Propositional Modal Logic

We consider second-order propositional modal logic (SOPML), an extension of the basic modal language with propositional quantifiers introduced by Kit Fine in 1970. We determine the precise expressive power of SOPML by giving analogues of the Van Benthem–Rosen theorem and the Goldblatt Thomason theorem. Furthermore, we show that the basic modal language is the bisimulation invariant fragment of SOPML, and we characterize the bounded fragment of first-order logic as being the intersection of first-order logic and SOPML.     

Towards a “Sophisticated” Model of Belief Dynamics. Part II: Belief Revision.

In the companion paper (Towards a “sophisticated” model of belief dynamics. Part I), a general framework for realistic modelling of instantaneous states of belief and of the operations involving them was presented and motivated. In this paper, the framework is applied to the case of belief revision. A model of belief revision shall be obtained which, firstly, recovers the Gärdenfors postulates in a well-specified, natural yet simple class of particular circumstances; secondly, can accommodate iterated revisions, recovering several proposed revision operators for iterated revision as special cases; and finally, offers an analysis of Rott’s recent counterexample to several Gärdenfors postulates [32], elucidating in what sense it fails to be one of the special cases to which these postulates apply.     

Most family physicians report communicating the risks of adverse drug reactions in words (vs. numbers)

Family physicians can communicate to patients the risk of adverse drug reactions using words or numbers, and this format has important implications for patients' ability to make informed decisions. The present study (a) assessed which formats family physicians preferred to communicate the risk of a given side effect, (b) tested whether the severity of this adverse drug reaction affected this preference, and (c) investigated the type of quantifiers physicians preferred to use in general (e.g., ratios, percentages). In a format selection task, a sample of 131 family physicians reported that they mostly use words to communicate to patients the risk of mild and severe adverse drug reactions, but the verbal preference was weaker for severe adverse drug reactions. The quantifier selection task showed that the most common quantifiers were verbal frequencies and verbal probabilities. Family physicians and patients should be aware of the implications of this preference.     

信息模糊：消费决策领域中的有限理性

信息模糊（obfuscation）是行为经济学研究的重要领域,主要解释了在商品买卖过程中,销售商通过把商品信息复杂化等手段,让人们的消费过程变得更加复杂和困难,从而使消费者在购买商品时面对信息模糊做出种种不明智的选择的现象问题。本文从以往的研究成果出发,就信息模糊、有限理性和销售者的决策行为的关系进行了探讨,以期为信息模糊的跨学科研究提供可借鉴的思路和方法。