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51.
This study measured students' attitudes toward a university's student health services (SHS) and identified factors that were related to their attitudes. A questionnaire surveying students' attitudes was administered to a sample of 150 students at the Oxford Campus of the University of Mississippi. Analysis of the data revealed that students' attitudes had a statistically significant correlation with the following variables: perceived medical care cost, amount of health information/education received during medical encounters, time spent in the waiting room of the SHS, sex of the student, and income of the student. There was no significant relationship between attitude and age.  相似文献   
52.
Three students with moderate handicaps were taught to initiate and expand on conversational topics. The teaching procedure used stimuli generated from actual conversations with nonhandicapped peers. Generalization was assessed by audiotaping conversations between the handicapped students and their peers in natural school contexts without adult supervision. Results indicated that training generalized to natural contexts. These results were socially validated by undergraduate special education students, who rated tapes of two of the students' conversations during training phases as more socially competent than during baseline. Results are discussed in terms of the evaluation of complex social behavior as multioperant behaviors.  相似文献   
53.
Questionnaires concerning attitudes toward use of microcomputers at home, in school, and at video arcades were administered to 879 high school students. Direct observations of adolescent proxemics and sex differences, and of various parameters of video games in 18 video arcades were made. A thorough and representative content analysis of sex bias of microcomputer software advertising brochures was carried out. Results supported previous findings of overrepresentation of masculine culture in the adolescent world of microcomputers, particularly regarding video games. Various types of computer-related activity were not related to socioeconomic class of the parents or to academic grades except for use of home microcomputers, which was mildly positively related to socioeconomic class (r = .124, p less than .001). Nearly half the activity in the arcades was strictly solitary. None of the arcade video games allowed for cooperative play. Most allowed only for sequential competition (86%) or simultaneous competition (7%); as many as 7% did not provide a display of the scores for a second player.  相似文献   
54.
A direct method in handling incomplete data in general covariance structural models is investigated. Asymptotic statistical properties of the generalized least squares method are developed. It is shown that this approach has very close relationships with the maximum likelihood approach. Iterative procedures for obtaining the generalized least squares estimates, the maximum likelihood estimates, as well as their standard error estimates are derived. Computer programs for the confirmatory factor analysis model are implemented. A longitudinal type data set is used as an example to illustrate the results.This research was supported in part by Research Grant DAD1070 from the U.S. Public Health Service. The author is indebted to anonymous reviewers for some very valuable suggestions. Computer funding is provided by the Computer Services Centre, The Chinese University of Hong Kong.  相似文献   
55.
56.
Visual control of step length during running over irregular terrain   总被引:1,自引:0,他引:1  
Running over uneven ground requires visually regulating step length to secure proper footing. To examine how this is achieved, we studied subjects running on a treadmill on a series of irregularly spaced targets. The movements of their lower limbs and coccyx relative to the targets were monitored opto-electronically by a Selspot system. The results indicated that step length was adjusted to strike the targets primarily by varying the vertical component of impulse applied to the ground during the stance phase. In contrast, horizontal impulse was not varied significantly, and changing the reach forward of the foot on landing contributed little to variation in step length. Changing the vertical impulse simply altered the step time proportionately. Thus the data are consistent with a time-based model in which vertical impulse is modulated by the optic variable delta tau (Lee, 1976) specifying the time gap that has to be bridged by the runner between two targets.  相似文献   
57.
Though the term “new technology” is widely used and discussed, there has been very little systematic study of attitudes to technology and their relation to other beliefs and group memberships. This article describes an initial investigation into the nature of attitudes towards new technology (n=534 undergraduates) and demonstrates that, as yet, these attitudes are only weakly structured and are not fully integrated with other social beliefs. General evaluations of the benefits of technological advance appear to be almost unrelated to beliefs about the inevitability of these advances or the desire to acquire training to deal with them. Contrary to popular expectations, evaluations of video games are unrelated to other beliefs about technology while other social beliefs are, as yet, only weakly integrated with these attitudes. This study also identifies gender differences in the assessment of potential benefits and highlights other differences attributable to academic group memberships. These finding are discussed with reference to the literature on sex-role stereotyping and group socialization processes.  相似文献   
58.
This study examined whether norms that concerning assisting frail older parents were different for daughters than for sons when the adult children are members of dual-earner couples. Data were gathered by telephone interviews from a probability sample of 315 adults residing in western Alabama. Of the 18 statements presented, statistically significant differences between the expectations for daughters and sons occurred in only three cases (help with housework, meal preparation, and yard work), suggesting substantial support for norms of equalitarianism. Further, there were few differences between the expectations held by females and by males for daughters and sons. Generally, the results suggested strong support for behaviors that facilitate the independent living of both adult children and their frail older parents.The authors acknowledge with thanks the assistance of the University of Alabama's Capstone Poll, which collected the data for this study.  相似文献   
59.
Effects of new types of reinforcement, alien type and alien combined with external type (double reinforcement), were examined in comparison with a conventional external one. One hundred and twenty children, 6th grade boys and girls, worked on learning discrimination tasks. Under alien reinforcement, upon correct responses of the child the experimenter received reinforcers from him-(or her-) self thus reinforcing the child responses. Under each condition, alien, external or double, children learned the tasks and their learning efficacy increased. Personality characteristics of children, in terms of extraversion and emotionality, differentiated effects of three reinforcement conditions on learning behavior and efficacy. The effect of alien reinforcement was influenced by the personality factors most, and that of double reinforcement least. In addition, personality factors influenced differently between alien and external conditions. Learning occurred differently under three different conditions of reinforcement, depending on the personality type of learners. Underlying mechanisms of alien reinforcement were different from, and its functions were independent of, those of external reinforcement. None of the effects of alien reinforcement on learning and motivation were contaminated by the intellectual faculties of learners.  相似文献   
60.
Maternal and adolescent depression are challenges that often co-occur. Many studies have drawn bivariate associations between maternal depressive symptoms, adolescent depressive symptoms, and family conflict, but few have examined reciprocal effects. Even among extant studies, there is a lack of clarity related to directionality of influence. Three competing theoretical models may explain the relationship between maternal depressive symptoms, adolescent depressive symptoms, and family conflict, and these processes may differ by adolescents’ sex. Using three time points of data from 187 diverse mother-adolescent dyads, we fit a taxonomy of autoregressive cross-lagged structural equation models to simultaneously evaluate the competing theoretical models and also examine differences by sex using multiple-group analyses. Results indicate a symptom-driven model whereby adolescent depressive symptoms predicted increases in family conflict. Sex differences were also found. For males, but not females, greater adolescent depressive symptoms predicted subsequent increases in maternal depressive symptoms, which then predicted lower family conflict—possibly indicating maternal disengagement/withdrawal. Our findings suggest addressing adolescent depressive symptoms in order to prevent family conflict and that distinctive targets for the prevention/intervention of family conflict should account for differences by adolescents’ sex.  相似文献   
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