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121.
Cross-sectional differences and longitudinal changes in cognitive functioning in relation to mortality across a 7-year follow-up period, with 3 times of measurement, were examined in a population-based sample of very old adults. The authors also sought to determine whether cause of death (cerebro/cardiovascular disease [CVD]; non-CVD) modified the magnitude of mortality-related cognitive deficits. Cognitive performance was indexed by tests of general cognitive ability, episodic memory, primary memory, verbal fluency, and visuospatial ability. Results indicated cross-sectional differences on all domains of functioning, with persons who would die within 3 years after baseline testing performing more poorly. Longitudinally, greater decrements were observed on all domains for persons who would die after the first follow-up period, as compared with survivors. Cause of death failed to modify the magnitude of the cross-sectional and longitudinal deficits. The pattern of results point to the general nature of this phenomenon. 相似文献
122.
The goal of the present studies was to construct and validate a short form of the 50-item Smoking Consequences Questionnaire (SCQ; T.H. Brandon & T. B. Baker, 1991), a measure of smoking outcome expectancies. In Study 1, a 21-item short form (S-SCQ) was derived from a sample of 107 young adults previously treated for substance abuse. In Study 2, the measure was cross-validated on 125 adolescents in treatment for substance abuse. Confirmatory factor analyses revealed good model fit and factorial invariance for the 4 S-SCQ subscales across both samples. Validation analyses on each sample found that subscale scores generally correlated significantly with smoking-related variables. The present studies provide initial evidence for the utility of the S-SCQ when used with young adults and adolescents. 相似文献
123.
Beyond the five-user assumption: Benefits of increased sample sizes in usability testing 总被引:1,自引:0,他引:1
It is widely assumed that 5 participants suffice for usability testing. In this study, 60 users were tested and random sets
of 5 or more were sampled from the whole, to demonstrate the risks of using only 5 participants and the benefits of using
more. Some of the randomly selected sets of 5 participants found 99% of the problems; other sets found only 55%. With 10 users,
the lowest percentage of problems revealed by any one set was increased to 80%, and with 20 users, to 95%. 相似文献
124.
Cameron P 《Psychological reports》1999,85(1):282-322
Counter to claims by the American Psychological Association and the National Association of Social Workers as well as numerous reviewers that children raised by homosexuals and married heterosexuals do not differ, the elaborate social-personality theory called "common sense" predicts that because "like produces like" and because psychopathy/sociopathy informs the major expressions of social deviance including homosexuality, children of homosexuals will (1) be more frequently subjected to parental instability (of residence and sexual partners) and (2) have poorer peer and adult relationships. Also, as is held to be true of their parents, homosexuals' children will be more apt to (3) become homosexual, (4) be unstable (have emotional problems and difficulty forming lasting bonds) with reduced interest in natality, and (5) be sexually precocious and promiscuous. Differences between homosexual and heterosexual comparison groups that bore on "common sense" were considered suggestive "bits" of empirical evidence. Differences that emerged within studies conducted by sympathetic researchers utilizing volunteer samples were considered bits of adverse evidence. Of 171 bits, 82 adverse and 55 nonadverse bits supported, while 34 bits fell against "common sense." From this tentative method of counting, support was found for common sense beliefs that children of homosexuals will be more apt to become homosexual and have poorer peer relationships, while weaker support was found for some of the other predictions. As assessed in this way, the empirical evidence in the literature tended to lean against claims of "no differences" between children raised by homosexuals and heterosexuals. In particular, the strongly worded official claims of there being "no differences" are overstatements. They amount to the organizations and some prominent researchers asserting that they have proven the null hypothesis, which is fundamentally impossible. It is likely that the nonsignificant statistical findings stressed thus far include Type Two errors created by use of volunteer samples, inadequate identification and measurement of likely differences, and refusal to interpret results in ways contrary to the sympathies of subjects, investigators, and the organizations. 相似文献
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Spatial diagram representations such as hierarchies, matrices, and networks are important tools for thinking. Our data suggest that college students possess abstract schemas for these representations that include at least rudimentary information about their applicability conditions. In Experiment 1, subjects were better able to select the appropriate spatial diagram representation for a problem when cued to use general category information in memory about those representations than when cued to use specific example problems given during the experiment. The results of Experiment 2 showed that the superior performance in the general category condition was not based on a comparison of the test problems with examples in memory. The results of Experiment 3 showed that the superior performance was not due to learning that occurred during the experiment or to transfer appropriate processing. The General Discussion section considers the nature of students' representation schemas and the question of why college students have only rudimentary schemas for common and widely applicable diagrammatic representations. 相似文献
129.
This study explores whether alternating betweenthe pronouns he and she ina text is an effective way to avoid sexist language.Participants were psychology students at a largemidwestern university and were predominately White and frommiddle-class backgrounds. Students read two versions ofan essay, one that alternated between masculine andfeminine pronouns and one that exclusively used paired, he or she-type pronouns. Readersperceived the alternating version to be biased in favorof females and lower in overall quality than the pairedversion. However, the alternating version appeared to be more effective at combating sexism,suggesting an alternating strategy may be desirable forauthors with this goal. If the author is not primarilyconcerned with increasing readers' awareness of gender issues, techniques such as pluralization or thesingular they may be moreappropriate. 相似文献
130.
Recent research on children's word learning has led to a paradox. Although word learning appears to be a deep source of insight into conceptual knowledge for children, preschoolers often categorize objects on the basis of shallow perceptual features such as shape. The current studies seek to resolve this discrepancy. We suggest that comparing multiple instances of a category enables children to extract deeper relational commonalities among category members. We examine 4-year-olds' categorization behaviors when asked to select a match for a target object (e.g., an apple) between a perceptually similar, out-of-kind object (e.g., a balloon) and a perceptually different category match (e.g., a banana). Children who learn a novel word as a label for multiple instances of the category are more likely to select the category match over the perceptual match. Children who learn a label for only one instance are equally likely to select either alternative. This effect is present even when individual target instances are more perceptually similar to the perceptual choice than to the category choice. We conclude that structural alignment processes may be important in the development of category understanding. 相似文献