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Baron and Ransberger (1978) argue that civil violence increases as temperature rises into the mid 80s, and then decreases as temperatures rise further. Two experiments test this hypothesis using data on temperature and the incidence of crime for summer months in two midwestern cities. The crime data were divided into violent and nonviolent crimes, and then correlated with the maximum, minimum, and average temperatures, and several humidity measures. Violent crime correlated significantly with temperature; nonviolent crime did not. This relationship was linear in the first study, but curvilinear in the second. Inspection of the data suggests that the incidence of aggressive behavior (i.e., violent crime) does not drop off in the mid-80s as laboratory findings and Baron and Ransberger's results would suggest, but continues to increase as temperatures rise into the 90s. The mean incidence of violent crime was higher for days in the 90s than for days in the 80s. A hypothesis for resolving this contradiction between real world and laboratory findings is discussed.  相似文献   
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The essay examines the argument advanced by E.D. Hirsch, Jr., for instituting ‘cultural literacy’ as a fundamental priority of schools. A number of confusions and equivocations in Hirsch's reasoning are identified, and the propensity of his project to indoctrinate is exposed. Among the features of Hirsch's argument shown to be troubling are his shifting construal of ‘language’, his inconsistency about the requirements of cultural literacy, and his uncritical relation to traditional images of the American past and present. The upshot is to raise the question why Hirsch's project has elicited wide support and praise.  相似文献   
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How can we explain that an assertion on something perceived can be understood in the same manner by somebody who cannot perceive that scene? This problem bases the interest in computational linguistics in how listener modeling could possibly be harmonized with reference semantics. Mental images substituting real perception appear as a way out. The architecture of the listener model has to be adapted to the creation and use of such pictorial data structures. Furthermore, the relation between the latter and a verbal (i. e., propositional) representation must be understood. The resulting architecture of a listener model with reference semantics can be employed to solve communicational problems from three general classes in a better way, as is demonstrated by an example implementation.  相似文献   
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To determine the relative impact of a number of family variables on children's performance of gender-typed household tasks, this study took account of the gender of the child, the gender of a sibling within the same age range (8–14 years), whether a first or second child and three parental variables: the degree of encouragement given to perform masculineand femininetasks, parental involvement in the same tasks, and parents' general egalitarianism. The sample consisted of 191 white, mainly Anglo Australian two-parent families, with the two oldest children in a boy—boy, girl—girl, boy—girl, or girl—boy sequence. To check on the robustness of effects, measures were taken on two occasions, on average 16 months apart. Among the family context variables, the gender of the child was the strongest contributing variable, with girls doing more feminine tasks than boys and boys doing more masculine tasks than girls. There was limited support for the proposition that first children do more housework than second children of the same gender, while the results for gender of sibling were small and inconsistent. Among the parental variables, encouragement had strong positive effects for feminine tasks (i.e., more encouragement by parents corresponded to more involvement by children). In contrast, parental involvement in the same tasks (modeling) and parental egalitarianism predicted only the performance of masculine tasks, and the direction of the effects was mostly negative (e.g., the more a father was involved in masculine tasks, the less a child did of those tasks). The results point to involvement in gender-typed activities being influenced by multiple factors, with parental encouragement and gender of child being most prominent among these. They also point to the value of sampling on more than one occasion and of considering separately the performance of feminine and masculine tasks. This research was financially supported by the Australian Research Council. We are happy to acknowledge that support, together with the essential assistance of the Department of Education and the many parents and children who participated in the study.  相似文献   
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It is shown that deterministic models can compete effectively with stochastic models in summarizing concept identification behavior. Three groups of deterministic models are examined. Examination of individual learners' trial by trial behavior in a concept experiment shows: (1) One person exhibited behavior consistent with a Hypothesis Permutation (HP) model despite being a nonlearner who showed no evidence of improvement over a period of 24 trials. However, when all 50 persons studied in each of two treatment groups were examined, only 22 members of one group and 10 of the other showed no inconsistencies with deterministic local consistency assumptions. (2) Certain deterministic computer programs could find at least one satisfactory order for predicting all responses by 18 of the 22 consistent solvers and 6 of the 10 consistent solvers, respectively, in the two groups just mentioned. For these 24 persons, then, a less restrictive deterministic model is adequate than for the others. (3) Those 38 original members of the first treatment group who met a stringent learning criterion were compared with respect to predictions generated by stochastic and mathematized deterministic models. One deterministic model (RSS-U 9-state) is in some respects the best of the models examined, but this success is a partial reflection of estimating eight parameters from the data.  相似文献   
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