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41.
This paper tests a meta-model of youthful marijuana use on students in Grades 11, 12 and 13. Although the specific models for each grade varied in detail, all followed a meta-model making the following assumptions: (1) that use or nonuse of marijuana depends primarily on attitude towards use; (2) that attitude largely reflects the perceived functional and dysfunctional consequences of use; and (3) that what people perceive as functional or dysfunctional depends on relevant personality characteristics. All three models showed satisfactory goodness-of-fit in terms of nonsignificant overidentification tests (minimum P > 0.25) and small discrepancies between observed correlations and the corresponding theoretically implied correlations. A notable feature of the Grade 13 data in contrast to those for Grade 12 and previously reported findings was the seeming unimportance of the perceived value of marijuana use for gaining acceptance from peers. It was suggested that this might reflect the selective survival into Grade 13 in the sampled community of more independently-oriented students.  相似文献   
42.
Life situations often seem to require dualistic, either or decision making, but this common method does not always clarify moral decisions. To show this, standard arguments on why to choose or not to choose the sex or ones child are presented. Then, our feminist thinking, which regards clusters of values, and which reframes questions rather than choosing between desirable alternatives, suggests another possibility, in a gynandrous world vision.  相似文献   
43.
It was hypothesized that male day care teachers who had adopted the feminine role of caregiver would score feminine in their personality traits and would reinforce children for feminine behaviors and punish them for masculine behaviors. A random sample of 20 male caregivers was contrasted to 20 male engineers on personality traits as assessed by The Adjective Checklist (ACL). Twenty female caregivers were also contrasted to the personality traits and the sex-typed contingency behaviors of the male caregivers. Feminine traits were defined by raw scores on the Abasement, Nurturance, Affiliation, Succorance, and Deference scales of the ACL. Masculine traits were represented by raw scores on the Achievement, Dominance, Endurance, and Autonomy scales. The Fagot-Patterson Checklist was employed to determine sex-typed contingency behaviors. Both male and female caregivers reinforced children significantly more for feminine behaviors than masculine behaviors (as defined by The Fagot-Patterson Checklist) and punished masculine behaviors more than feminine behaviors. The personalities of the male caregivers corresponded to the feminine direction of their female counterparts, but they were not significantly more feminine than the male engineers. The female caregivers, however, scored significantly more feminine in personality than the male engineers.This study is based on a dissertation submitted by Bryan E. Robinson to the Department of Child Development — Family Relations, University of North Carolina at Greensboro, in partial fulfillment of the requirements for the Ph.D.  相似文献   
44.
材料数量与呈现速度对视、听同时瞬时记忆的影响   总被引:3,自引:0,他引:3  
视、听材料同时识记、瞬时记忆效果并非普遍降低。材料数量影响视、听同时瞬时记忆效果的变化及其方向;无意义联系汉字数量超记忆广度时,视、听同时瞬时记忆相对效果与非同时识记相比提高。材料数量也影响视、听同时瞬时记忆的相对优势及重现方式。这些结果倾向于表明,材料数量在记忆广度内及超记忆广度时,视、听同时瞬时记忆的组织加工不同。呈现速度只影响记忆优势及重现方式。根据多项分析,可以认为视、听通道标签是组织视、听同时瞬时记忆最鲜明的标签,经过识记5个视、听同时字表,视、听同时识记效果有提高趋势。  相似文献   
45.
Statistical significance tests are derived and evaluated for measuring apparent differences between an obtained and an expected binormal ROC curve, between two independent binormal ROC curves, and among groups of independent binormal ROC curves. A binormal ROC curve is described by two parameters which represent the spread of the means and the ratio of the standard deviations of the two underlying Gaussian decision variable distributions. To test the significance of apparent differences between or among ROC curves, approximate χ2 statistics for each of the three tests were constructed from maximum likelihood estimates of the two parameters defining the binormal ROC curve. The performance of each test statistic was evaluated by simulating five-category rating scale data with equal numbers of noise and signal-plus-noise trials (set at 50, 250, and 500) for each of three typical ROC curves. For the significance test involving only one ROC curve, rating scale data were generated from the chance diagonal of the ROC space also. Although test performance was found to be somewhat dependent on the number of trials and on the location of the ROC curve in the ROC space, comparisons of the obtained and expected fractions of (falsely) significant results at various α levels showed the proposed statistical significance tests to be reliable under practical experimental conditions.  相似文献   
46.
This study examined the location and rate of stuttering in the spontaneous speech of nine young stutterers (4.0–6.6 yr) in relation to certain aspects of syntax. It was designed to answer the following questions: Is there more stuttering at clause onset (boundary) than at other points in the clause? Does the type of clause influence rate of stuttering? Is there more stuttering on complex than on simple sentences? The syntactic analysis defined 10 clause types (seven pertaining to complex sentences and three pertaining to simple sentences); clause boundaries (taking into account “filler” words occuring in such positions); and hierarchical constituent structure within sentences. Stuttering was found with significantly greater frequency at clause boundaries than at internal (nonboundary) positions of clauses. This was apparent for nine of the 10 clause types, the exception being complement clauses. The word “and” at the beginning of simple and complex sentences provoked a high rate of stuttering. The hierarchical structure within the clause did not influence the location of stuttering, and sentence complexity was not a factor in the rate of stuttering.  相似文献   
47.
A method for identifying eggs laid by different subsections or individual members of groups of domestic hens is described. Fat-soluble dyes are placed in gelatin capsules and fed to selected birds. These dyes produce discrete colored bands in the yolks of eggs laid by those birds. The presence of dye in eggs can be detected through the shell, and different patterns of rings can be distinguished by boiling and sectioning eggs. Application of the method to other species and other circumstances is considered.  相似文献   
48.
Thirty-six 3- and 4-year-old children were given a battery of six metalinguistic tasks and two measures of language development: the Peabody Picture Vocabulary Test and a sentence comprehension test. The results clearly showed that the majority of preschoolers were able to make at least some metalinguistic judgments, and that metalinguistic performance improved with age. Furthermore, overall performance on the metalinguistic tasks was significantly correlated with each language measure when the effects of age were partialed out. In contrast, the correlation between age and metalinguistic performance was not significant once the effects of both language measures were partialed out. These data demonstrate that preschoolers' metalinguistic abilities are more extensive than has been previously acknowledged, and that they are closely tied to other aspects of language development at this time.  相似文献   
49.
50.
This study investigated auditory discrimination as a function of ethnic group membership within the same socioeconomic status (SES). Subjects were 126 randomly selected six-year-old students attending schools in the lower SES community of southeast San Diego. Only students with no known speech or hearing defects and of normal intelligence were included. They were assigned to one of three categories: Black, Chicano, or Anglo.Subjects were administered four tests in a counterbalanced design: the Wepman, the Gross, and the Ott. The latter two were developed for use with Black dialect and Spanish-speaking youngsters, respectively. The ANOVA results indicated a reliable difference between the main effects of the groups (F=40.34,p<.001) and tests (F=72.82, p<.001), with a significant interaction between tests and groups (F=44.91, p<.001). Interaction effects were evaluated with the Dunn theorem. Significant differences were found among Anglo, Black, and Chicano students on the discrimination list for Spanish sounds (Ott) and a significant Anglo/Black difference on the discrimination test for Black dialect (Gross). Contrary to previous findings, there were no differences between the groups on the Wepman Test of Auditory Discrimination (WTAD). However, there are significant differences between groups on separate items of this test.  相似文献   
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