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981.
982.
The present study examined observers’ ability to discriminate canonical and dynamically anomalous collisions that were presented in either frictionless or frictional systems. Whereas previous research has provided qualitative demonstrations that dynamic information can be extracted from visual events, the current study provides a parametric assessment of observers’ sensitivity to dynamic invariants. Our findings indicate that observers are competent when viewing both familiar, terrestrial (frictional) systems and unfamiliar but computationally simpler, 0-G (frictionless) systems. Thus, our sensitivity to these dynamic invariants in visual events is robust in natural systems whose dynamic properties differ from those of the environment in which we evolved and developed. 相似文献
983.
A technique is described in which line-drawn pictures can be rapidly interlaced, allowing for sequential part presentation or tachistoscopic presentation on the Apple II. This is accomplished using a two-stage process in which the pictorial stimuli are converted into machine code data files and then used to create a rapidly changing display consisting of two or more line drawings. The latter stage could be accomplished in less than 2 msec but is limited by the frame time of the monitor (17–20 msec). 相似文献
984.
Normative data are presented for the probability of successfully completing 192 single-solution word fragments. Normative data on the familiarity of college students with the solution words are also given, along with estimates of word frequency from existing norms. Regression analyses were performed in order to predict fragment completion difficulty from familiarity, frequency, and several structural characteristics of the fragments. Familiarity, whether or not first and/or last letters appeared in the fragment, and the ratio of letters to missing letters in the fragment were included in the regression equation as significant predictors of difficulty for this fragment set. 相似文献
985.
All seven variables of containment theory were operationalized for questionnaires. Data were collected from 677 adolescents in a variety of high schools and correctional institutions, and divided into categories by race and sex. Factor analysis indicated that the structure of the relationships among the seven containment variables and delinquency was substantially different among black females. 相似文献
986.
The purpose of this study was to ascertain which sex education topics parents of preadolescents regarded as appropriate for their children. The sample was comprised of 146 respondents randomly selected from a class list of sixth graders in a suburban school district. A mailed, self-administered questionnaire listing 48 possible topics was used to elicit parental response. Pretesting found the questionnaire to be highly reliable (Cronbach's alpha = .95). Overall, parents strongly supported the inclusion of a broad range of sex education topics regardless of parental age, sex, marital status, income, education, or child's sex. Moreover, parents were largely in agreement with the inclusion of sensitive topics in addition to those which were more physiological or behavioral. Catholics more often than Protestants agreed with the inclusion of birth control, abortion, and sterilization even after controlling for income and education. Thus, the findings suggest that parents of sixth graders find a broad sex education program in the school appropriate. To this end, school officials and sex educators should not overlook the needs of preadolescents for sex education solely on the basis of perceived parental opposition. 相似文献
987.
The prevalence of DSM-III conduct and adjustment disorders in two adolescent psychiatric facilities, both located near large U.S. cities, was investigated. Overall, 31.6% of the adolescent inpatients were conduct disordered while 12.5% were adjustment disordered. The conduct disorders were primarily "aggressive" subtypes suggesting that this characteristic may influence hospitalization and diagnostic decisions. Such data on prevalence assists future treatment planning, allowing anticipation of case loads. 相似文献
988.
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
989.
This research evaluated the effects of involvement of adolescents in community service activities on levels of alienation. It was proposed that alienation could be reduced through the implementation of a model which utilized community service activities to facilitate adolescent access to adult society, development of responsibility, collaborative and cooperative work, and control over planning and outcomes. It is suggested that adolescent involvement in service activities can produce positive benefits, among which are reduced levels of alienation, improved school behavior, improved grade point average, and acceptance by the adult community. These findings also suggest that females respond more positively to school when allowed to problem-solve collectively and collaboratively. 相似文献
990.
Factors associated with juvenile detention truancy 总被引:1,自引:0,他引:1
Factors influencing truancy from a juvenile court treatment facility were investigated. Youth born in 1962 (N = 124) who were placed in the facility were compared for number of truancies, background, and personality variables. Results showed that males with prior adjudication for home or school truancy had a 65% probability of eloping from the court facility as compared to a 34% probability for youth adjudicated for other offenses. Most females were adjudicated for truancy offenses and showed a 62% probability of truancy while in the court facility. Further, for females who eloped and were returned, the probability of a subsequent truancy was above 80%. Personality characteristics of truants varied with sex: male truants were more likely to be conduct disordered youth for which impulsivity and disregard for social norms is prevalent; female truants appear more likely to be in conflict over autonomy issues. 相似文献