The comparison problem for approximating epistemic ideals

Some epistemologists think that the Bayesian ideals matter because we can approximate them. That is, our attitudes can be more or less close to the ones of our ideal Bayesian counterpart. In this paper, I raise a worry for this justification of epistemic ideals. The worry is this: In order to correctly compare agents to their ideal counterparts, we need to imagine idealized agents who have the same relevant information, knowledge, or evidence. However, there are cases in which one's ideal counterpart cannot have one's information, knowledge, or evidence. In these situations, agents cannot compare themselves to their ideal counterpart.     

心理学对经济学的涉入——从理性自利到社会偏好的决策框架

理性认知能力与社会偏好存在紧密的关联。文章简要回顾了经济决策理论从理性模型到有限理性模型和社会偏好模型的发展进程,论述了人们理性的局限性及其根源,并进一步探讨理性认知能力与社会偏好的关系。对人类以及灵长目动物的研究显示,有限理性可能是由根源于演化的适应性机制所导致。人类不公平厌恶的起源、个体公平能力的发展规律和表征公平的大脑结构上的证据表明,理性认知能力能让人更好地抑制自私性,实现更高层次的公平。     

Observed Variability and Values Matter: Toward a Better Understanding of Information Search and Decisions from Experience

The search for different options before making a consequential choice is a central aspect of many important decisions, such as mate selection or purchasing a house. Despite its importance, surprisingly little is known about how search and choice are affected by the observed and objective properties of the decision problem. Here, we analyze the effects of two key properties in a binary choice task: the options' observed and objective values, and the variability of payoffs. First, in a large public data set of a binary choice task, we investigate how the observed value and variability relate to decision‐makers' efforts and preferences during search. Furthermore, we test how these properties influence the chance of correctly identifying the objectively maximizing option, and how they affect choice. Second, we designed a novel experiment to systematically analyze the role of the objective difference between the options. We find that a larger objective difference between options increases the chance for correctly identifying the maximizing option, but it does not affect behavior during search and choice. Copyright © 2013 John Wiley & Sons, Ltd.     

Identification and Testing of Modes in Beliefs

Characterizing diversity in beliefs is of paramount importance in empirical research on human behavior. In game theory, the focus is on the hypothesis formation. We present a data set with ideal properties for characterizing such diversity. The data consist of hypotheses on the empirical distribution of opponent choices. Using nonparametric techniques, we identify modes in the data corresponding to subpopulations of behavioral types and find the statistical significance of these modes in the underlying population distribution.     

快速节俭启发式--基于有限理性和生态理性的简单决策规则

本文阐述了德国“马克斯．普朗克人类发展研究所”以Gerd Gigerenzer教授为代表的“适应行为与认知中心”简称“ABC研究中心(组)”关于判断、推理和决策制定简单启发式研究的理论背景、研究思路和技术路线,着重介绍了该研究中心在有限理性和生态理性假设基础上提出的一系列极富创意的快速节俭启发式规则,并对围绕这些简单决策规则开展的研究活动作了简要介绍。     

Towards a “Sophisticated” Model of Belief Dynamics. Part I: The General Framework

It is well-known that classical models of belief are not realistic representations of human doxastic capacity; equally, models of actions involving beliefs, such as decisions based on beliefs, or changes of beliefs, suffer from a similar inaccuracies. In this paper, a general framework is presented which permits a more realistic modelling both of instantaneous states of belief, and of the operations involving them. This framework is motivated by some of the inadequacies of existing models, which it overcomes, whilst retaining technical rigour in so far as it relies on known, natural logical and mathematical notions. The companion paper (Towards a “sophisticated” model of belief dynamics. Part II) contains an application of this framework to the particular case of belief revision. Presented by Hannes Leitgeb     

LÉVY HIERARCHY IN WEAK SET THEORIES

We investigate the interactions of formula complexity in weak set theories with the axioms available there. In particular, we show that swapping bounded and unbounded quantification preserves formula complexity in presence of the axiom of foundation weakened to an arbitrary set base, while it does not if the axiom of foundation is further weakened to a proper class base. More attention is being paid to the necessary axioms employed in the positive results, than to the combinatorial strength of the positive results themselves.     

Symmetric Propositions and Logical Quantifiers

Symmetric propositions over domain and signature are characterized following Zermelo, and a correlation of such propositions with logical type- quantifiers over is described. Boolean algebras of symmetric propositions over and Σ are shown to be isomorphic to algebras of logical type- quantifiers over . This last result may provide empirical support for Tarski’s claim that logical terms over fixed domain are all and only those invariant under domain permutations.