Entailment with Near Surety of Scaled Assertions of High Conditional Probability

An assertion of high conditional probability or, more briefly, an HCP assertion is a statement of the type: The conditional probability of B given A is close to one. The goal of this paper is to construct logics of HCP assertions whose conclusions are highly likely to be correct rather than certain to be correct. Such logics would allow useful conclusions to be drawn when the premises are not strong enough to allow conclusions to be reached with certainty. This goal is achieved by taking Adams" (1966) logic, changing its intended application from conditionals to HCP assertions, and then weakening its criterion for entailment. According to the weakened entailment criterion, called the Criterion of Near Surety and which may be loosely interpreted as a Bayesian criterion, a conclusion is entailed if and only if nearly every model of the premises is a model of the conclusion. The resulting logic, called NSL, is nonmonotonic. Entailment in this logic, although not as strict as entailment in Adams" logic, is more strict than entailment in the propositional logic of material conditionals. Next, NSL was modified by requiring that each HCP assertion be scaled; this means that to each HCP assertion was associated a bound on the deviation from 1 of the conditional probability that is the subject of the assertion. Scaling of HCP assertions is useful for breaking entailment deadlocks. For example, it it is known that the conditional probabilities of C given A and of ¬ C given B are both close to one but the bound on the former"s deviation from 1 is much smaller than the latter"s, then it may be concluded that in all likelihood the conditional probability of C given A B is close to one. The resulting logic, called NSL-S, is also nonmonotonic. Despite great differences in their definitions of entailment, entailment in NSL is equivalent to Lehmann and Magidor"s rational closure and, disregarding minor differences concerning which premise sets are considered consistent, entailment in NSL-S is equivalent to entailment in Goldszmidt and Pearl"s System-Z ⁺. Bacchus, Grove, Halpern, and Koller proposed two methods of developing a predicate calculus based on the Criterion of Near Surety. In their random-structures method, which assumed a prior distribution similar to that of NSL, it appears possible to define an entailment relation equivalent to that of NSL. In their random-worlds method, which assumed a prior distribution dramatically different from that of NSL, it is known that the entailment relation is different from that of NSL.     

Confidence in judgments based on incomplete information: An investigation using both hypothetical and real gambles

This study assessed how confidence in judgments is affected by the need to make inferences about missing information. Subjects indicated their likelihood of taking each of a series of gambles based on both probability and payoff information or only one of these sources of information. They also rated their confidence in each likelihood judgment. Subjects in the Explicit Inference condition were asked to explicitly estimate the values of missing information before making their responses while subjects in the Implicit Inference condition were not. The manner in which probability information was framed was also manipulated. Experiment 1 employed hypothetical gambles and Experiment 2 employed gambles with real money. Expressed likelihood of taking gambles was higher when probability was phrased in terms of '% chance of winning' rather than '% chance of losing', but this difference was somewhat less with real gambles than with hypothetical gambles. Confidence ratings in each experiment were actually higher on incomplete information trials than on complete information trials in the Explicit Inference condition. Results were related to the general issue of confidence in judgments.     

Quantity-based judgments in the domestic dog (<Emphasis Type="Italic">Canis lupus familiaris</Emphasis>)

We examined the ability of domestic dogs to choose the larger versus smaller quantity of food in two experiments. In experiment 1, we investigated the ability of 29 dogs (results from 18 dogs were used in the data analysis) to discriminate between two quantities of food presented in eight different combinations. Choices were simultaneously presented and visually available at the time of choice. Overall, subjects chose the larger quantity more often than the smaller quantity, but they found numerically close comparisons more difficult. In experiment 2, we tested two dogs from experiment 1 under three conditions. In condition 1, we used similar methods from experiment 1 and tested the dogs multiple times on the eight combinations from experiment 1 plus one additional combination. In conditions 2 and 3, the food was visually unavailable to the subjects at the time of choice, but in condition 2, food choices were viewed simultaneously before being made visually unavailable, and in condition 3, they were viewed successively. In these last two conditions, and especially in condition 3, the dogs had to keep track of quantities mentally in order to choose optimally. Subjects still chose the larger quantity more often than the smaller quantity when the food was not simultaneously visible at the time of choice. Olfactory cues and inadvertent cuing by the experimenter were excluded as mechanisms for choosing larger quantities. The results suggest that, like apes tested on similar tasks, some dogs can form internal representations and make mental comparisons of quantity.     

The microanalysis of fixed-interval responding

The fixed-interval schedule of reinforcement is one of the more widely studied schedules in the experimental analysis of behavior and is also a common baseline for behavior pharmacology. Despite many intensive studies, the controlling variables and the pattern of behavior engendered are not well understood. The present study examined the microstructure and superstructure of the behavior engendered by a fixed-interval 5- and a fixed-interval 15-minute schedule of food reinforcement in the pigeon. Analysis of performance typical of fixed-interval responding indicated that the scalloped pattern does not result from smooth acceleration in responding, but, rather, from renewed pausing early in the interval. Individual interresponse-time (IRT) analyses provided no evidence of acceleration. There was a strong indication of alternation in shorter-longer IRTs, but these shorter-longer IRTs did not occur at random, reflecting instead a sequential dependency in successive IRTs. Furthermore, early in the interval there was a high relative frequency of short IRTs. Such a pattern of early pauses and short IRTs does not suggest behavior typical of reinforced responding as exemplified by the pattern found near the end of the interval. Thus, behavior from clearly scalloped performance can be classified into three states: postreinforcement pause, interim behavior, and terminal behavior.     

Hemispheric differences in semantic-relatedness judgments

Subjects judged the semantic relatedness of word pairs presented to the left or right visual field. The word pairs were presented one below the other. On critical trials, the words' referents had a typical spatial relation, with one referent oriented above the other (e.g. ATTIC/BASEMENT). The spatial relation of the words either matched or mismatched the spatial relation of their referents. When presented to the left hemisphere, the match or mismatch did not have an effect. However, there was a reliable mismatch effect for pairs presented to the right hemisphere. The results are interpreted in the context of perceptual theories of mental representation.     

The accidental transgressor: morally-relevant theory of mind

To test young children’s false belief theory of mind in a morally relevant context, two experiments were conducted. In Experiment 1, children (N = 162) at 3.5, 5.5, and 7.5 years of age were administered three tasks: prototypic moral transgression task, false belief theory of mind task (ToM), and an “accidental transgressor” task, which measured a morally-relevant false belief theory of mind (MoToM). Children who did not pass false belief ToM were more likely to attribute negative intentions to an accidental transgressor than children who passed false belief ToM, and to use moral reasons when blaming the accidental transgressor. In Experiment 2, children (N = 46) who did not pass false belief ToM viewed it as more acceptable to punish the accidental transgressor than did participants who passed false belief ToM. Findings are discussed in light of research on the emergence of moral judgment and theory of mind.     

Biases in social comparisons: Optimism or pessimism?

Social comparisons typically lead to two kinds of biases: A comparative optimism bias (i.e., a tendency for people to view themselves as more likely than others to be the beneficiaries of positive outcomes) or a comparative pessimism bias (i.e., a tendency for people to view themselves as less likely than others to be such beneficiaries); rarely are people fully calibrated in terms of how they compare to others. However, there is little systematic research on the factors that determine when a comparative optimism versus pessimism bias will occur, how they can be attenuated and whether such attenuation is always desirable. In this paper, we report four studies which demonstrate the following key results: First, we show that perceived level of control over the outcome drives whether a comparative optimism or pessimism bias will occur (Study 1). Second, an increase in perceived similarity between self and a comparison target person attenuates the comparative optimism bias in domains that people view as highly controllable (Study 2a) and attenuates the comparative pessimism bias in domains that people view as less controllable (Study 2b). Finally, we show that people are willing to work harder when they experience more comparative optimism in higher control scenarios and when they experience less comparative pessimism in lower control scenarios, illustrating that motivating people to strive harder for positive outcomes can result from exacerbated or attenuated bias, depending on the context (Study 3).     

What coping tells about personality

In this study, 123 participants (non‐psychology students) who responded to an interpersonal stress situation staged in the laboratory were judged by unacquainted observers in terms of the Big Five dimensions, intelligence and social attractiveness. Coping behaviour appeared to predict personality impressions in a way that mirrors the relations between personality and coping observed in previous research: Overall, higher levels of Extraversion (E), Agreeableness (A), Conscientiousness (C) and Openness to experience (O) (as well as intelligence and social attractiveness) were predicted by problem‐focussed behaviour and cognitive restructuring, whereas higher levels of Neuroticism (N) were predicted by withdrawal/passivity. The interpersonal impact of the particular coping reactions, as indicated by a positive personality impression, were largely inconsistent with their impact on affect following the stress induction. Copyright © 2009 John Wiley & Sons, Ltd.     

Metacognitive Judgments and Control of Study

ABSTRACT— Recent evidence indicates that people's judgments of their own learning are causally related to their study behavior and not epiphenomenal. I argue here that people use these metacognitions in an effort to selectively study material in their own region of proximal learning. First they attempt to eliminate materials that are already well learned. Then they progress successively from studying easier to more difficult materials. Successful implementation of this metacognitively guided strategy enhances learning. The necessary components are, first, that the metacognitions be accurate, and second, that the appropriate choices are implemented for study. With these parts in place, the individual is in position to effectively take control of his or her own learning.     

学习判断与学习时间分配的关系

学习判断与学习时间分配的关系是元认知领域的重要问题, 对学习判断的研究在于使个体了解自己的学习和记忆活动, 从而有效控制学习过程, 合理分配学习时间, 这是元记忆监测影响控制的典型例子。近来有研究者提出学习时间分配不仅表现控制功能, 而且还表现监测功能。于是围绕学习时间的双重功能, 他们提出了元记忆监测与控制至少存在两种关系模型—— MC(监测影响控制)模型和CM(控制影响监测)模型, 后来又提出了两模型相互协同作用的合并动态模型—— 连续波浪型模式和同时发生模型。未来的研究应在继续验证MC模型和完善CM模型的基础上, 尝试检验两模型的合并动态模型。