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981.
982.
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   
983.
Cornell University Medical College, Westchester Division, The New York Hospital, White Plains, New York It is well established that there is a complex timekeeping mechanism in the human brain. This mechanism is associated with a variety of physiological and psychological rhythms having a period of about a day, and thus referred to as circadian rhythms. The circadian system has recently been modeled in terms of two underlying oscillators, one much more resistant to changes in routine than the other. These oscillators are considered to be endogenous, that is, internal to the organism, and not reliant for their existence upon changes in the person’s environment or general behavior. They thus continue to run even when the sleep/wake cycle is suspended, as in sustained operations. Thus, by their very nature, sustained operations require the individual to override the inputs that are coming from his or her circadian system (especially the indication that sleep is required). The aim of this paper is to provide a background to the area of circadian rhythms research, including a section on the methodology, so that the impact of the circadian system on sustained operations can be better understood.  相似文献   
984.
Holland's theory of congruence of work environments was examined by analyzing the career redirection of 62 men of managerial and professional level who changed occupations between the ages of 33 and 54. Three-letter personality codes for each subject were obtained by administering the Strong-Campbell Interest Inventory. Dictionary of Occupational Titles codes for first and second occupation were obtained and then translated into Holland codes. These were compared to the personality code for each man to determine whether the first or second job was more congruent. It was found that 26 men changed to careers more congruent with their personality, 25 to careers less congruent, and 11 made no change. The results of the study do not lend support to Holland's theory, probably because of the imprecision of DOT categories for research purposes. The need for a more reliable means for coding work environments is discussed.  相似文献   
985.
986.
Expectancy theory concepts were used to predict (a) the attractiveness of, (b) the amount of effort directed toward entering, and (c) the eventual choice of a job in relatively big and small work organizations. It was found, among a group of graduating seniors from a technical college, that antecedent perceptions regarding organizational size (expectancy, valence, instrumentality) were significantly related to the relative attractiveness of different-sized organizations and the number of job interviews taken with relatively big and small companies. In addition, economically tied extrinsic outcomes were seen as more readily attainable in big organizations, whereas certain intrinsic outcomes were perceived to be more easily obtained in small organizations.  相似文献   
987.
Although vocational psychologists and sociologists have a long history of researching occupational choice, their theoretical postures have almost always been shaped in light of information on males, with little consideration for females. This article is an addition to others which attempt to correct this shortcoming in the literature. The article reviews the dominant conceptual schemes used to study occupational choice, considers potentially female-specific variables, and provides a typology for the analysis of women's marital-familial statuses and work modes.  相似文献   
988.
In order to study the influence of style and subject matter on the development of children's art preferences, 60 randomly selected subjects from three grade levels, with an equal number of males and females, were shown ten color slides of paintings representing five categories of subject matter and two broad categories of style. Results indicated that style was the dominant variable at each grade level, and consistently accounted for more of the overall variance than subject matter. Unexpectedly, no appreciable developmental differences were evident in preference judgments across grade levels observed in this study.  相似文献   
989.
In a dichotic listening situation stimuli were presented one at a time and at random to either ear of the subject at constant inter-stimulus intervals of 800 msec. The subject's task was to detect and count occasional slightly different stimuli in one ear. In Experiment 1, these ‘signal’ stimuli were slightly louder, and in Experiment 2 they had a slightly higher pitch, than the much more frequent, ‘standard’, stimuli. In both experiments signals occured randomly at either ear. Separate evoked potentials from three different locations were recorded for each of the four kinds of stimuli (attended signals, unattended signals, attended standards, unattended standards). Contrary to Hillyard et al. (1973), no early (N1 component) evoked-potential enhancement was observed to stimuli to the attended ear as compared with those to the unattended ear, but there was a later negative shift superimposed on potentials elicited by the former stimuli. This negative shift was considered identical to the N1 enhancement of Hillyard and his colleagues which in the present study was forced, by the longer inter-stimulus interval used, to demonstrate temporal dissociation with the N1 component. The ‘Hillyard effect’ was, consequently, explained as being caused by a superimposition of a CNV kind of negative shift on the evoked potential to the attended stimuli rather than by a growth of the ‘real’ N1 component of the evoked potential.  相似文献   
990.
This paper reports the results of a panel study of young, white, rural women from Georgia, South Carolina, and Texas (N = 138). The study was primarily concerned with how social origin variables affected early educational and occupational orientations and how early states of these orientations affected the orientations themselves at a later point in time. The results indicated that mother's education had a greater effect than father's education, but in either case the effect is mediated by intervening influences such as early aspirations and expectations. These young women held very traditional status orientations (with 60% projecting the occupations of beautician, nurse, stenographer, or school teacher), and their orientations were quite stable between their sophomore and senior years in high school. Since there has been so little work reported on the status attainment process for women, and rural women in particular, this study does offer a limited insight into this phenomenon.  相似文献   
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