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991.
Peter Gärdenfors 《Studia Logica》1987,46(4):321-327
The purpose of this note is to formulate some weaker versions of the so called Ramsey test that do not entail the following unacceptable consequenceIf A and C are already accepted in K, then if A, then C is also accepted in K. and to show that these versions still lead to the same triviality result when combined with a preservation criterion. 相似文献
992.
To be pertinent to democratic practice, collective choice functions need not apply to all possible constellations of individual preference, but only to those that are humanly possible in an appropriate sense. The present paper develops a theory of humanly possible preference within the context of the mathematical theory of learning. The theory of preference is then exploited in an attempt to resolve Arrow's voting paradox through restriction of the domain of majoritarian choice functions. 相似文献
993.
Charles G. McClintock Frank J. Stech James K. Beggan 《European journal of social psychology》1987,17(4):447-464
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
994.
Following a left CVA, a skilled professional typist sustained a disturbance of typing disproportionate to her handwriting disturbance. Typing errors were predominantly of the sequencing type, with spatial errors much less frequent, suggesting that the impairment was based on a relatively early (premotor) stage of processing. Depriving the subject of visual feedback during handwriting greatly increased her error rate. Similarly, interfering with auditory feedback during speech substantially reduced her self-correction of speech errors. These findings suggested that impaired ability to utilize somesthetic information--probably caused by the subject's parietal lobe lesion--may have been the basis of the typing disorder. 相似文献
995.
Comprehension of connected language as assessed by the Revised Token Test (RTT) was studied in 17 children with left hemisphere lesions (LL) and 11 with right hemisphere lesions (RL). LL children's significantly lower performance on several subtests than left controls (LC) matched by age, sex, race, and social class appeared to be related to the memory demands of these subtests rather than the limited syntactic elements assessed by the RTT. LL subjects requested significantly more command repetitions than control or RL subjects and when a repetition was not requested LL subjects often responded with immediacy. Although RL children tended to perform lower than right matched controls (RC), these differences were not significant nor readily related to either the memory or specific linguistic structures assessed. RL subjects required fewer command repetitions than LL subjects and exhibited a significantly greater frequency of immediate responses than controls or LL subjects. While based on few children, a trend for LL children with retrorolandic lesions to perform more poorly than those with left prerolandic lesions was suggested. No systematic difference in performance was apparent for children with left cortical vs. left subcortical lesions or among discrete sites of lesions within the right hemisphere. Children with left lesions prior to 1 year of age performed no better and, in several instances, significantly poorer than LL patients sustaining lesions after 1 year of age. Among RL subjects, those sustaining lesions after 1 year of age had greater difficulty than those with lesion onset before 1 year of age, especially on linguistic elements which seemed to be dependent upon visual spatial properties. Further studies are needed to evaluate the comprehension of more complex linguistic structures among children with unilateral brain lesions as well as to study the role of more basic factors such as memory and attention in explaining the present findings. 相似文献
996.
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
997.
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
998.
Douglas Cullinan Kenneth D. Gadow Michael H. Epstein 《Journal of abnormal child psychology》1987,15(4):469-477
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
999.
Kevin D. Stark William M. Reynolds Nadine J. Kaslow 《Journal of abnormal child psychology》1987,15(1):91-113
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
1000.
Modulation of male urogenital sniff, attack, and mount behaviors by urinary cues from female mice (SJL/J) was assessed in two experiments. Experiment 1 examined the efficacy of urine from ovariectomized and intact females in modulating the behavior of sexually experienced and inexperienced males vis-à-vis the control substance, water. It was found that urine from ovariectomized females showed no behavior-modulating properties, whereas urine from intact females decreased attack but increased sniff and mount behaviors in male mice. These findings are indicative of ovarian-dependent chemosignals contained in the urine of only intact females. Prior sexual experience had no effect on behavior of males when exposed to urine from ovariectomized females. Sniff and mount behaviors were, however, increased when sexually experienced males were exposed to urine from intact females. Using sexually inexperienced males, Experiment 2 assessed the chemosignal activity of urine from females in each of four estrous phases. It was determined that urine from proestrous and estrous females increased sniff and mount behaviors and decreased attack behavior. Urine from metaestrous females was shown to possess only sniff-inducing and mount-reducing chemosignal properties. Urine from females in diestrous lacked attack- and mount-modulating chemocues but may possess a sniff-inducing chemosignal. 相似文献