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971.
A new method for determining the minimum number of observations per subject needed to achieve a specific generalizability coefficient is presented. This method, which consists of a branch-and-bound algorithm, allows for the employment of constraints specified by the investigator.  相似文献   
972.
In 1977 sex-trait stereotypes in Norway were measured at the young adult level and at the level of five-year-olds. At the young adult level the Adjective Check List was used, and the results were analysed according to an affective meaning scoring system, and a scoring system based on Transactional Analysis. The instrument used for children was a picture-story technique (Sex Stereotype Measure II). Persistence and change in sex-trait stereotypes were examined by replicating the study in 1987. Quantitatively, young adults' sex-trait stereotypes seemed to have changed little during the last decade, but qualitative analyses indicated that stereotypes have changed in the direction of greater favourability, activity and strength towards women and in the reverse direction towards men. The children in the 1987 sample expressed less stereotype knowledge than children in the 1977 sample concerning traits which traditionally have been ascribed to men.  相似文献   
973.
C. Barry Jay 《Studia Logica》1989,48(3):389-393
The internal language of a monoidal category yields simple proofs of results about a natural numbers object therein.  相似文献   
974.
Working in the fragment of Martin-Löfs extensional type theory [12] which has products (but not sums) of dependent types, we consider two additional assumptions: firstly, that there are (strong) equality types; and secondly, that there is a type which is universal in the sense that terms of that type name all types, up to isomorphism. For such a type theory, we give a version of Russell's paradox showing that each type possesses a closed term and (hence) that all terms of each type are provably equal. We consider the kind of category theoretic structure which corresponds to this kind of type theory and obtain a categorical version of the paradox. A special case of this result is the degeneracy of a locally cartesian closed category with a morphism which is generic in the sense that every other morphism in the category can be obtained from it via pullback.The financial support of the Royal Society in London is gratefully acknowledged.  相似文献   
975.
976.
Massey on fallacy and informal logic: A reply   总被引:1,自引:0,他引:1  
Ralph H. Johnson 《Synthese》1989,80(3):407-426
  相似文献   
977.
DBA/2J mice were monaurally or binaurally tested for susceptibility to sound-induced seizure. Two seconds following the beginning of running, one group of binaurally tested mice had acoustic stimulation interrupted for 15 s. These mice later seized when the stimulation was readministered. Their seizure progression closely resembled the behavior exhibited by noninterrupted binaurally stimulated mice and did not shift to the biphasic motor pattern of monaurally stimulated subjects. We conclude that the single burst of running of a binaurally tested mouse is qualitatively different from either of the two bursts of running exhibited by monaurally tested mice.  相似文献   
978.
The relationship between amphetamine-induced stereotyped behavior and a neuroendocrine index of arousal, plasma corticosterone (CCS), was investigated. 6-Hydroxydopamine lesions of the caudate-putamen, which produced dopamine depletions of 60%, blocked stereotypy and prolonged the elevation in corticosterone associated with d-amphetamine treatment (5 mg/kg). Similar dopamine depleting lesions of the nucleus accumbens, which attenuated the locomotor, but not the stereotypic, response to AMPH did not have this effect on CCS. This pattern of results supports the hypothesis that stereotypy has a coping function which may serve to alter arousal and further suggests important differences between the nigrostriatal and mesolimbic dopamine projections in modulating the responsiveness of the neuroendocrine system. These results have implications for understanding the function of behavioral stereotypies common to a number of psychopathological conditions, including schizophrenia and childhood autism.  相似文献   
979.
Two experiments were conducted to examine the hypothesized differential effectiveness of two attentional focusing strategies in pain perception. In the first experiment, subjects (72 male college students) rated their levels of pain after being exposed to either low- or high-intensity pressure stimulation for 75 s. Subjects were instructed to use either an external or internal focus of attention during the pain induction. Results revealed that external focusing was more effective for coping than internal focusing across both levels of stimulus intensity. The second experiment was a replication of the first, and featured bolstered internal focusing and stimulus intensity manipulations. Results showed that high-intensity stimulation produced higher pain ratings than did low-intensity stimulation for subjects in the internal focusing conditions, but not for those in the external focusing conditions. The findings support the power of distraction strategies for dealing with short-term pain with a rapid onset. Theoretical implications are discussed.The authors thank Darwyn E. Linder and Daniel M. Landers for their help in development of this research. The authors are also indebted to Sarah Colley, Jona Davis, Nanci Neuberger, and Rebecca Roberts for their assistance in data collection.  相似文献   
980.
A number of studies have demonstrated stable individual differences in the cues that generate emotions and other feeling states. These differences are assumed to arise from the cues parents use to identify their children's emotional states. As children learn about their own emotional states, they come to rely on these same cues. To test one implication of their view, the facial expressions of children (N=41) were manipulated and their feelings assessed. Some children reported emotions consistent with their expressions, while others reported emotions appropriate to the situation. In a separate procedure, their mothers were asked to identify the emotional states of children whose expressions were inconsistent with an account of their circumstances. Mothers who paid more attention to their children's expressive behavior had children who were more responsive to their own expressive behavior. In contrast, the mothers who were more responsive to situational cues had children whose emotions arose from the situational cues as well.The authors would like to thank numerous teachers and administrators of the Worcester Public School system in Worcester, Massachusetts, for their assistance.  相似文献   
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