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841.
The conclusions derived by Keynes in his Treatise on Probability (1921) concerning induction, analogical reasoning, expectations formation and decision making, mirror and foreshadow the main conclusions of cognitive science and psychology.The problem of weight is studied within an economic context by examining the role it played in Keynes' applied philosophy work, The General Theory (1936). Keynes' approach is then reformulated as an optimal control approach to dealing with changes in information evaluation over time. Based on this analysis the problem of inductive justification, from a societal perspective, is not, What can we rationally believe will occur in the economic future, given our past experiences? but Can we make the future so as to attain specific economic goals with practical certainty? An answer requires that restrictions be placed on the methodological individualist approach and the acceptance of a restricted holistic approach.  相似文献   
842.
The course of bargaining is determined in part by interdependent individuals exchanging messages so as to influence other's behaviour, and thereby to increase the likelihood of achieving outcomes consistent with their own goals. The communication of threats and promises are two major message strategies that are employed to influence the behaviour of others in a bargaining relationship. The present study examines the effects of players' level of commitment to these forms of message strategies upon behaviour in a duopoly bargaining task. Past research has oprationalized commitment in terms of the consistency with which an individual has followed through on threats or promises in the past. In the present research, Becker's (1960) concept of a side-bet is employed to provide an alternative means for defining and manipulating commitment. A side-bet obtains when either a threatener or a promiser posts a valued resource, say a bond, which they forfeit if they do not follow through on their stated threat or promise. The main expectations of the present study were that increased commitment to threat meassages would lead to more competitive behaviour and outcomes within a duopoly bargaining task, whereas increased commitment to promise messages would produce more cooperative behaviour and outcomes. Partial support for these major expectations, as well as confirmation of a number of secondary expectations, was obtained.  相似文献   
843.
Four reading-related, information-processing tasks were administered to right-handed blind readers of braille who differed in level of reading skill and in preference for using the right hand or the left hand when required to read text with just one hand. The tasks were letter identification, same-different matching of letters that differed in tactual similarity, short-term memory for lists of words that varied in tactual and phonological similarity, and paragraph reading with and without a concurrent memory load of digits. The results showed interactions between hand preference and the hand that was actually used to read the stimulus materials, such that left preferrers were significantly faster and more accurate with their left hands than with their right hands whereas right preferrers were slightly but usually not significantly faster with their right hands than with their left hands. In all cases, the absolute magnitude of the left-hand advantage among left preferrers was substantially larger than the right-hand advantage among right preferrers. The results suggest that encoding strategies for dealing with braille are reflected in hand preference and that such strategies operate to modify an underlying but somewhat plastic superiority of the right hemisphere for dealing with the perceptual requirements of tactual reading. These requirements are not the same as those of visual reading, leading to some differences in patterns of hemispheric specialization between readers of braille and readers of print.  相似文献   
844.
This paper presents the results of a study of active/passive sentence comprehension by a Polish-speaking agrammatic aphasic. The patient showed good performance on canonically ordered active and passive structures, but performed poorly on inverted variants. The systematically normal and deviant comprehension patterns observed are accounted for by normal interpretative strategies applied to syntactic structures built around verbs with reduced inflectional morphology. The differences between our Polish data and the English data discussed in the literature are explained by the fact that Polish possesses a richer derivational verb morphology. The interpretation of inverted sentences demonstrates the importance of S-V-O word order preference. Our analysis draws upon the notion of grammatical functions to explain the data.  相似文献   
845.
Regional cerebral blood flow (rCBF) may be measured with inhalation techniques that use end-expired values of radioactivity to estimate the isotope concentration in arterial blood. These end-expired data are used as an input function in a mathematical equation to derive rCBF. End-expired air is assumed normally to be in equilibrium with the arterial blood at the alveolar surface of the lung during regular (passive) breathing; this assumption may not be valid during continuous phonation. We therefore have analyzed breathing (inhalation/exhalation) patterns and end-expired radioactivity (133Xe) during (1) speaking, (2) singing, and (3) humming of the national anthem, and also during (4) passive breathing. Statistically significant differences in breathing patterns were measured between a group of nonmusicians and two groups of musicians (singers) during the phonation tasks: The nonmusicians breathed more often (and more rapidly) and exhibited less variability in their breathing patterns than did the musicians. Notwithstanding these differences, the shapes of smoothed functions derived from the end-expired values were not influenced appreciably during phonation (except possibly during talking). The latter finding suggests that estimates of rCBF derived with these data should not be confounded seriously because of the continuous phonation.  相似文献   
846.
Strengthening local alcohol programs so as to emphasize primary prevention is an active concern among mental health professionals; yet interventions intended to achieve this aim have produced only modest shifts in program orientation in most communities. An analysis of data obtained from those active in local affairs in a small community, using Q-sort techniques, suggested that contrasting perspectives toward alcohol abuse as a social problem may stand as an unseen barrier to relevant change.  相似文献   
847.
Psychotropic drug treatment in learning-disabled (LD), educable mentally retarded (EMR), and seriously emotionally disturbed (ED) children and adolescents receiving public school special education services was examined. The findings indicated that while treatment prevalence rates for EMR and ED groups were comparable, the rate for LD students was much lower. In the LD sample, pharmacotherapy was associated with higher ratings of behavioral deviance, longer placement in special education, less social integration, and greater peer rejection, which suggests that symptom severity is an important determiner of pharmacotherapy in this population.  相似文献   
848.
This study evaluated the clinical validity of the Intellectual Screening, Development, and Achievement scales of the Personality Inventory for Children-Revised (PIC-R), as well as the newly derived PIC-R Factor IV scale, in identifying cognitive impairment in a clinic-referred sample of preschoolers. The clinical validity of these PIC-R subscales was also compared to that of the Minnesota Child Development Inventory (MCDI). The results showed that the PIC-R scales and Factor IV were reasonably successful in identifying cognitively impaired preschoolers, but much less successful in identifying cognitively normal preschoolers. Overall, the MCDI was the most successful in correctly identifying the preschoolers' cognitive status.  相似文献   
849.
Subjects making lexical decisions are reliably faster in responding to high-frequency words than to low-frequency words. This is known as the word frequency effect. We wished to demonstrate that some portion of this effect was due to frequency differences between words rather than to other dimensions correlated with word frequency. Three groups of subjects (10 engineers, 10 nurses, and I0 law students) made lexical decisions about 720 items, half words and half nonwords, from six different categories (engineering, medical, low-frequency nontechnical, medium-frequency nontechnical, and two groups of high-frequency nontechnical). Results of two analyses of variance revealed a crossover interaction such that engineers were faster in responding to engineering words than to medical words, whereas nurses were faster in responding to medical words than to engineering words. The engineering and medical words were equally long and equally infrequent by standard word counts. We take this as support for a frequency-based component in the word frequency effect. The practical implications of this research for estimating the readability of technical text are discussed.  相似文献   
850.
Twenty-nine children 9 to 12 years old who were identified as moderately to severely depressed using the Children's Depression Inventory were randomly assigned to either a self-control, behavioral problem-solving, or waiting list condition. The self-control treatment focused on teaching children self-management skills. The behavioral problem-solving therapy consisted of education, self-monitoring of pleasant events, and group problem solving directed toward improving social behavior. Subjects were assessed pre-and posttreatment and at 8-week follow-up with multiple assessment procedures and from multiple perspectives. At posttreatment, subjects in both active treatments reported significant improvement on self-report and interview measures of depression while subjects in the waiting list condition reported minimal change. Results were maintained at follow-up. The general success of the experimental treatments was discussed and recommendations for further treatment components were provided.Second authorship on this article is shared by Drs. Reynolds and Kaslow. The authors would like to thank Mr. Ed Guzwieski, Principal, and the teachers of Oregon Middle School for their cooperation with this study. The authors also would like to thank Mary Wysopal for conducting the posttreatment and follow-up interviews, and Carol Fairbanks for rating the audiotapes.  相似文献   
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