On the law of Regular Minimality: Reply to Ennis

Ennis's critique touches on issues important for psychophysics, but the points he makes against the hypothesis that Regular Minimality is a basic property of sensory discrimination are not tenable.(1) Stimulus variability means that one and the same apparent stimulus value (as measured by experimenter) is a probabilistic mixture of true stimulus values. The notion of a true stimulus value is a logical necessity: variability and distribution presuppose the values that vary and are distributed (even if these values are represented by processes or sets rather than real numbers). Regular Minimality is formulated for true stimulus values. That a mixture of probabilities satisfying Regular Minimality does not satisfy this principle (unless it also satisfies Constant Self-Similarity) is an immediate consequence of my 2003 analysis. Stimulus variability can be controlled or estimated: the cases when observed violations of Regular Minimality can be accounted for by stimulus variability corroborate rather than falsify this principle. In this respect stimulus variability is no different from fatigue, perceptual learning, and other factors creating mixtures of discrimination probabilities in an experiment.(2) Could it be that well-behaved Thurstonian-type models are true models of discrimination but their parameters are so adjusted that the violations of Regular Minimality they lead to (due to my 2003 theorems) are too small to be detected experimentally? This is possible, but this amounts to admitting that Regular Minimality is a law after all, albeit only approximate: nothing in the logic of the Thurstonian-type representations per se prevents them from violating Regular Minimality grossly rather than slightly. Moreover, even very small violations predicted by a given class of Thurstonian-type models can be tested in specially designed experiments (perhaps under additional, independently testable assumptions). The results of one such experiment, in which observers were asked to alternately adjust to each other the values of stimuli in two observation areas, indicate that violations of Regular Minimality, if any, are far below limits of plausible interpretability.     

情绪对个体判断和决策影响研究概述

情绪对个体判断和决策影响已经成为目前的一个研究热点。情感启发式、决策情感理沦等为研究情绪对个体判断和决策的影响提供了一定的理论基础．而近期提出的“风险作为情感”假设为研究提供了较为全面的理沦框架。此外,个体差异比较、时间压力以及信息激起为研究情绪在个体判断和决策中的作用提供了很好的研究思路。     

Confidence in own and others' knowledge

A person's confidence judgement of a statement reflects his/her degree of belief in the correctness of that statement. Deficient ability to assess the correctness of statements (or beliefs) can have serious consequences in many situations. This study compares the realism (calibration) of subjects' confidence ratings in two situations ( n = 64). The first situation was when the subjects confidence rated their own answers to general knowledge questions. The second was when the subjects gave confidence ratings of another person's answers to general knowledge questions. The results show that subjects were more poorly calibrated and were more overconfident in the second situation, i.e. when they gave confidence ratings of answers given by another person, compared with when they rated their own answers. The data further indicates that the results can not be explained in terms of the amount of cognitive processes invested when making the confidence judgements. For example, the subjects rated the other person's answers to questions they had answered themselves, and to questions they had not seen before. No differences in confidence or in calibration and other measures of judgmental realism were found between these two categories of questions. Nor did instructions to imagine the thought process of the other person improve any of these measures. The subjects disagreed with the other person's answer on 23% of all occasions. Significantly poorer calibration was shown where subjects disagreed with the other person than where they agreed. Contents of a social nature attended to by the subjects may have affected the results. The results, when related to previous research in the area, give rise to the question of how the social situation can be arranged to achieve the best calibration.     

Time pressure and the application of decision rules: Choices and judgments among multiattribute alternatives

The effects of time pressure on decisions and judgments were studied and related to the use of different decision rules in a multiattribute decision task. The decision alternatives were students described by their high school grades in Swedish, Psychology and Natural Science. The subjects were asked to choose the student they thought would be most able to follow a university program and graduate as a school psychologist. On the basis of earlier findings using the same kind of decision task (Svenson et al., 1990) it was hypothesised that subjects under time pressure would prefer candidates having the maximum grade across all attributes to a greater extent than subjects under no time pressure. Furthermore, it was hypothesised that subjects under time pressure would also focus more on the most important attribute and choose the alternatives being best on that attribute. The results supported these hypotheses.     

Are preference reversals reduced when made explicit?

Previous research has shown that preferences for options, such as gambles, can reverse depending on the response mode. These preference reversals have been demonstrated when tasks were performed sequentially. That is, subjects completed one task before beginning another. In an attempt to eliminate preference reversals, we asked subjects to perform tasks simultaneously. That is, subjects made two types of responses for each pair of gambles before evaluating the next pair. In the condition with no financial incentives, preference reversal rates were slightly reduced. In another condition, subjects were paid for their participation and they were allowed to play a gamble with real monetary compensation. A gamble pair was randomly selected, and if a subject's responses in the two tasks were consistent for that pair, he or she was allowed to play the ‘preferred’ gamble. Otherwise, the experimenter selected the gamble from the pair. With these financial incentives, systematic preference reversals were eliminated for two of the three task combinations. Preference reversals continued to occur for attractiveness ratings versus selling prices, although, even for that pair of tasks, the reversal rate was significantly reduced. For all three task pairs, preference orders from the two tasks appeared to merge into more consistent orders.     

Calibration of sensory and cognitive judgments: Two different accounts

The purpose of this study was to test predictions of two recent theories of realism of confidence. Ecological approaches to realism of confidence in one's general knowledge (Gigerenzer et al. , 1991; Juslin, in press a ; Björkman, in press) predict good calibration or, in the case of poor cognitive adjustment, overconfidence, within the cognitive domain. The subjective distance theory of confidence in sensory discriminations (Björkman et al. , 1992) predicts a pervasive underconfidence bias for sensory discriminations. Empirical data are reported showing that: (a) Calibration for sensory judgments is considerably poorer than calibration for well adapted cognitive judgements, a difference that can be entirely traced to underconfidence in the sensory domain. (b) While an initial overconfidence bias in the cognitive domain is removed by outcome feedback, the bias observed in sensory discriminations is unaffected even by a prolonged feedback session. It is suggested that the nature of confidence in sensory discriminations is different from the nature of confidence in cognitive judgments.     

The analysis of experience: John Dewey and Elsie Ripley Clapp on desire and thinking, 1911

Unpublished correspondence with Elsie Ripley Clapp, along with extensive notes for a 1911 course, The Analysis of Experience, provide the context for a consideration of John Dewey's discussion of the relation between desire and thinking. Dewey's philosophic point of view is portrayed as it was developing in his own mind. The unity of thought and desire, the necessity of making objects of inquiry, the identification of thinking and acting, are themes in these materials which would appear in their published form in such works as Essays in Experimental Logic, Democracy and Education, and Human Nature and Conduct. In the unpublished materials, Dewey is seen as a naturalist at work in his laboratory, reworking his ideas and acknowledging Clapp's assistance in getting Dewey to connect practical situations in life with the philosophic distinctions under development. The 1911 materials are an excellent connection between problematics in Dewey's earlier writings on ethics, epistemology, and logic, and his later writings, on the same subjects in the 1920's and 1930's.     

Quantity representation in children and rhesus monkeys: linear versus logarithmic scales

The performances of 4- and 5-year-olds and rhesus monkeys were compared using a computerized task for quantity assessment. Participants first learned two quantity anchor values and then responded to intermediate values by classifying them as similar to either the large anchor or the small anchor. Of primary interest was an assessment of where the point of subjective equality (PSE) occurred for each species across four different sets of anchors to determine whether the PSE occurred at the arithmetic mean or the geometric mean. Both species produced PSEs that were closer to the geometric mean for three of four anchor sets. This indicates that monkeys and children access either a logarithmic scale for quantity representation or a linear scale that is subject to scalar variability, both of which are consistent with Weber's law and representation of quantity that takes the form of analog magnitudes.