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821.
Thorne DR Johnson DE Redmond DP Sing HC Belenky G Shapiro JM 《Behavior research methods》2005,37(1):111-118
This field-portable reaction time test and analysis software run on devices using the Palm operating system. It is designed
to emulate a test and commercial device widely used in sleep deprivation, shift work, fatigue, and stimulant drug research
but provides additional capabilities. Experimental comparisons with the standard commercial device in a 40-hour total sleep
deprivation study show it to be comparably sensitive to selected experimental variables. A Pocket PC-compatible version is
under developement. 相似文献
822.
This study examined changes in body image and predictors of body dissatisfaction during pregnancy. It was expected that higher levels of depression, social comparison tendencies, teasing, societal pressure to be thin and public self-consciousness would predict body dissatisfaction prospectively. Healthy pregnant women (n = 128) completed questionnaires on three occasions during their pregnancies reporting on a total of four time points: 3 months prior to pregnancy (retrospectively reported), in the early to mid-second trimester, the late-second/early-third trimester, and the latter part of the third trimester. For the most part women reported adapting to the changes that occurred in their body; however, women were most likely to experience higher levels of body dissatisfaction in early to mid-second trimester. Findings related to predictors of body dissatisfaction revealed that both social and psychological factors contributed to body image changes in pregnancy. Implications of the findings are discussed. 相似文献
823.
824.
Leonard S. Feldt 《Psychometrika》1969,34(3):363-373
An approximate statistical test is derived for the hypothesis that the reliability coefficients (Cronbach's ) associated with two measurement procedures are equal. Control of Type I error is investigated by comparing empirical sampling distributions of the test statistic with the theoretical model derived for it. The effect of platykurtosis in the test-score distribution on the test statistic is also considered. 相似文献
825.
Doubly self-embedded sentences, differing only in whether the relative pronouns were present or deleted, were presented to two groups of Ss who were required to respond to a word beginning with a particular letter in each sentence and to paraphrase the sentence. The results of both the phoneme monitor task and the paraphrase task indicated that comprehension was better when the relative pronouns were present than when they were deleted. These results are consistent with earlier results for the paraphrase task but are not consistent with earlier results for the phoneme monitor task. Possible reasons for the inconsistency were considered. It was concluded that the phoneme monitor task does reflect comprehension difficulty in a manner consistent with the paraphrase task and that deleting the relative pronouns does make comprehending self-embedded sentences more difficult. 相似文献
826.
827.
Using samples from Iowa OASI sub-populations, the relationships between NMZ scores and the criteria of acceptance for services by the Iowa DVR as well as future rehabilitation of clients were examined. The results suggest that (a) the relationship of NMZ scores to the acceptance criterion is low; (b) the relationship of NMZ scores to the more ultimate criterion of client rehabilitation is moderate, and, here, empirical weights appear to work better than the intuitive weights assigned in the original development of NMZ scores; (c) through empirical weighting, the variable of age was revealed as most important in predicting such criteria. 相似文献
828.
829.
Most existing models assume that negative moods are more likely than positive moods to (a) induce recall of negatively toned information, (b) lead to less favorable evaluations, (c) induce more systematic but less flexible processing, and (d) arouse a desire to change the mood. A series of studies is discussed in which each of these effects and its opposite are obtained. The consistent pattern of data in these studies supports a configural, as opposed to a simple hedonistic or associationistic, view of mood. From the configural perspective, people do not seek positive moods; they seek positive outcomes. And, in some contexts, these outcomes can be signaled by a negative mood. 相似文献
830.
E. Jane Costello Stephen C. Messer Hector R. Bird Patricia Cohen Helen Z. Reinherz 《Journal of child and family studies》1998,7(4):411-432
The goal of these analyses was to use existing data to provide an empirically-based estimate of the prevalence in the population of Serious Emotional Disturbance (SED) in children and adolescents, to assist States in their task, required under PL 102-321, of including such estimates in their applications for Block Grant funds. Seven data sets were identified that could provide estimates of SED. The principal investigators agreed on common definitions of the key components of SED: a psychiatric diagnosis and significant functional impairment. Two definitions of impairment were used: domain-specific (impairment in one or more of three areas of functioning) and global (in the worst 10% over all). They also defined a set of correlates and risk factors for SED: age, gender, race/ethnicity, and poverty. Investigators then reanalyzed their own data, using these standard definitions, and calculated the proportion of SED youth who received mental health care. The median estimate of SED with global impairment was 5.4%, with a range from 4.3% to 7.4%. Estimates of SED with domain-specific impairment ranged from 5.5% to 16.9% (median 7.7%). Rates were slightly higher in boys. There were no clear ethnic differences. Poverty doubled the risk of SED. Only one SED child in four had recently received mental health care. Estimates of SED are critically dependent on the method used to define diagnosis and functional impairment. Using common definitions, seven studies produced fairly consistent estimates, which were similar to the estimate of prevalence of Serious Mental Illness (SMI) in adults. Implications for the estimate of State-by-State prevalence rates are discussed. 相似文献