跨期选择的认知机制与神经基础

跨期选择是指个体对发生在不同时间的成本与收益进行权衡的决策过程。跨期选择的计算模型从经济学的角度用数学模型来建构时间折扣函数,而认知成分模型则从心理学的角度来研究跨期选择中的心理效应与认知成分。跨期选择的神经基础有三种不同的研究取向：双机制加工取向、单机制加工取向、自我控制取向。未来研究应该在跨期选择的认知机制、神经通路及运行机制、跨期选择的应用,以及从进化的角度对人与动物的跨期选择行为进行更深入的研究。     

跨期选择中偏好反转的心理机制

通过直接测量近期和远期选择中备选项激活的情绪、间隔的时间知觉及对备选项金额差异和时间间隔的重视程度,以探究跨期选择中偏好反转产生的心理机制。结果表明：（1）近期选择中,备选项激活的情绪强度差异显著,而远期选择中两者的差异不显著;（2）近期和远期选择中,情绪强度差异和时间知觉差异能够预测偏好反转的发生。研究结果支持了偏好反转的情绪激活差异假说和时间知觉差异假说。     

The effect of constant outcome value on judgments and decision making given linguistic probabilities

Two experiments were performed to determine whether judgments of the relative chances of two independent events occurring are biased by constant outcome values contingent on the events when the uncertainties are specified by linguistic expressions (e.g. doubtful). In Experiment 1, subjects directly judged the relative chances of the two events, of which one was represented by a spinner and the other by a linguistic probability expression. In Experiment 2, only linguistic probability expressions were used to describe the two events and a betting procedure was used. A bias was evident in both studies, such that the relative judgments tended to favour the event with the positive rather than the negative contingent outcome. The bias was smaller for the low- than for the high-probability phrases. Individual differences were great, with the bias appearing strongly in only about one-third of the population. Theoretical implications of the present and related results are discussed.     

Arguments in the practical reasoning underlying constructed probability responses

Reasoning is an important cognitive activity in probability assessment, and one that has been understudied. This proposition motivates the paper's three general aims. First, based on research in rhetoric, we present a theoretical means of analyzing the arguments constructed during the reasoning that occurs in probability assessment. Second, from verbal protocol data, we establish that subjects constructed arguments in forming beliefs and assessing the associated probabilities. Third, we analyze the data for the structure of subject's arguments, including argument content and form. Subjects used a limited amount of relevant evidence and used a variety of argument forms that could be characterized by the nature of the knowledge that subjects brought to bear in forming the arguments. Subjects predominantly used causal reasoning, but also employed hierarchical category knowledge, resemblance relationships, and arguments from authority. These findings form a basis for expanding our accounts of probability assessment and for improving assessment practice.     

What determines biological fitness? The problem of the reference environment

Organisms’ environments are thought to play a fundamental role in determining their fitness and hence in natural selection. Existing intuitive conceptions of environment are sufficient for biological practice. I argue, however, that attempts to produce a general characterization of fitness and natural selection are incomplete without the help of general conceptions of what conditions are included in the environment. Thus there is a “problem of the reference environment”—more particularly, problems of specifying principles which pick out those environmental conditions which determine fitness. I distinguish various reference environment problems and propose solutions to some of them. While there has been a limited amount of work on problems concerning what I call “subenvironments”, there appears to be no earlier work on problems of what I call the “whole environment”. The first solution I propose for a whole environment problem specifies the overall environment for natural selection on a set of biological types present in a population over a specified period of time. The second specifies an environment relevant to extinction of types in a population; this kind of environment is especially relevant to certain kinds of long-term evolution.     

To do or not to do? A cognitive consistency model for drawing conclusions from conditional instructions and advice

This paper investigates a cognitive consistency model of the directionality of conditional instructions and advice that use probability expressions to express uncertainty about the antecedent p. The proposed model combines world knowledge (conveyed by causal direction) with linguistic information (conveyed by polarity and negation), and predicts whether the complex sentence antecedent has a positive or negative directionality, which in turn predicts whether a positive or negative conclusion q will be drawn. The first experiment uses Do q if p conditionals to show that given a consequent q participants complete antecedents p with a probability expression in line with expected sentence directionality. The second experiment uses If p then do q conditionals to show similar effects in a reverse direction. A third experiment uses If p then do q conditionals to show that participants draw conclusions predicted by the cognitive consistency model but not by a decision-theoretic approach to reasoning.     

Adding possibilities can reduce the Gambler's Fallacy: A naïve-probability paradox

This paper reports a novel paradox of intuitive probabilistic reasoning detected in naïve reasoners’ responses in two separate experiments where we manipulated the number of sets (or possibilities) of the problem keeping constant the probability of the critical set. Experiment 1 showed that the incidence of the Gambler's Fallacy (GF) was reduced when the number of sets was increased. In Experiment 2, a reduction of the GF also occurred but, more importantly, the percentage of correct responses of the participants increased when three sets of possibilities instead of two were used. Therefore, both Experiments 1 and 2 demonstrated that an increase in the extensional complexity of a problem can, under certain circumstances, lead to facilitation. These results support the importance of the extensional features in solving chance problems and are consistent with the model theory of reasoning.     

Good things come to those who wait: Time discounting differences between adult offenders and nonoffenders

Criminal behavior has been explained by the idea that offenders have a lack of self-control. Yet, Wilson and Daly reported that juvenile offenders exhibit time-discounting tendencies similar to those of nonoffending juveniles. As no previous study has compared time-discounting behavior of adult offenders with nonoffenders, we raise the question, do adult offenders exhibit shorter time horizons or the tendency to discount future rewards? To answer this question, 89 offenders (ex-prisoners and prisoners) and 106 nonoffenders completed a time-discounting measure containing 27 different monetary choices. Our results show that, counter to findings with juvenile offenders, adult offenders (ex-prisoners) exhibit significantly shorter time horizons and discount more than nonoffenders as delayed payoffs increase to medium and large rewards. Furthermore, both offenders and nonoffenders are less likely to discount as the reward of future gains increases to medium and large.     

Measuring coherence

This paper aims to contribute to our understanding of the notion of coherence by explicating in probabilistic terms, step by step, what seem to be our most basic intuitions about that notion, to wit, that coherence is a matter of hanging or fitting together, and that coherence is a matter of degree. A qualitative theory of coherence will serve as a stepping stone to formulate a set of quantitative measures of coherence, each of which seems to capture well the aforementioned intuitions. Subsequently it will be argued that one of those measures does better than the others in light of some more specific intuitions about coherence. This measure will be defended against two seemingly obvious objections.