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991.
The confluence model of intellectual development was estimated for a within-family sample of 321 children from 101 transracial adoptive families. Mental ages of the children and their parents, as well as birth or adoption intervals, were used in a nonlinear least-squares estimation procedure to obtain children's predicted mental ages. Contrary to an earlier report using these data, the confluence model performed quite well, accounting for up to 50% of the variance in mental age. When the relationship between chronological and mental age was taken into account, the predictive power of the model was reduced but not eliminated. The confluence model was also fitted separately to various subsamples. The model generated a good fit to the data from both biological and adopted children and fit the data from early-adopted children much better than the data from later-adopted children. Both findings were taken as evidence that the confluence model provides an environmental account of intellectual development within the family. 相似文献
992.
The purpose of this study was to quantify social interaction rhythms in 3- and 5-month-old term and preterm infants and their mothers. Infant-mother dyads were videotaped in a 3-min face-to-face paradigm. For each second of the interaction, separate scores were assigned to infant and mother indicating levels of affective involvement, creating 2 180-sec time series. Spectral and cross-spectral techniques were used to quantify periodicities in each member of the dyad and to estimate the synchrony or coherence of interactional rhythms between each infant and mother. Results showed the existence of periodicities in the behavior of each infant and mother at 3 and 5 months, with most subjects showing spectral peaks between .022 and .10 Hz. Increases from 3 to 5 months in behavioral periodicities were found for infants and mothers as well as for the coherence between infant-mother dyads. Term dyads showed higher coherence than preterm dyads at both 3 and 5 months. Term infants more often led the interaction at both ages. These results were taken as evidence that behavioral periodicities, which may be biologically based, underlie early mother-infant interaction and provide a temporal structure for the organization of cognitive and affective experience. Differences in synchrony between term and preterm infants may explain later reported differences in language between these groups. 相似文献
993.
Richard E. Clark 《Educational technology research and development : ETR & D》1985,33(4):249-262
A thirty percent sample of the computer-based instruction (CBI) studies meta-analyzed by Kulik et al was examined for evidence of confounding. The purpose of the analysis was to explore the validity of competing claims about the contribution of the computer to measured achievement gains found in CBI studies. Some of these claims propose that CBI effects are overestimated and others argue that CBI effects are underestimated. The result of the analysis strongly suggests that achievement gains found in these CBI studies are overestimated and are actually due to the uncontrolled but robust instructional methods embedded in CBI treatments. It is argued that these methods may be delivered by other media with achievement gains comparable to those reported for computers. Construct validity cautions are offered for those who wish to use meta-analytic results as evidence for implementing CBI in schools and for the design of future CBI research. 相似文献
994.
The present paper examines whether there is significant variation in schooling outcomes between Scottish secondary schools, and if so, how much is associated with pupil intake, and how much is associated with the schools they attend. It also examines whether schools vary in their effectiveness for different types of pupils, and whether schools tend to be superior, or inferior, across three different outcome measures. The study employed a subsample of data from the 1977 Scottish School Leavers Survey on over 700 pupils from 15 schools in one administrative division. These data were linked to data on the verbal reasoning quotients of the pupils, derived from a test administered to them before they entered secondary school. For each of the 15 schools we estimated the expected scores on measures of English, arithmetic and overall attainment for pupils with below average, average, and above average ability, controlling for pupils’ verbal ability, gender, prestige of father's occupation, mother's education, and number of siblings. The study shows there was wide variation in schooling outcomes between secondary schools in the division, even after controlling for family background characteristics and pupil ability prior to entering secondary school. There were few schools that were particularly effective for low ability pupils, but not high ability pupils and vice versa. Schools tended to be effective, or ineffective, across all three outcome measures. 相似文献
995.
Two core subjects in operations and strategic management have been developed for the final year of a Bachelor of Business (Management) degree. The subjects are interrelated and emphasise experiential learning. Objectives of the subjects are presented, and the reasons for their experiential emphasis given. Experiential exercises for some topics are briefly described, together with an assessment of their worth and the reasons for their development. The exercises include a work study of leggo block construction, role plays, environmental scanning, industrial negotiations, and a business simulation that threads through both subjects. 相似文献
996.
Steven J. Rakow 《科学教学研究杂志》1985,22(4):289-302
The study was designed to investigate the influence of student characteristics and classroom characteristics on students' inquiry skill. The sample consisted of a national stratified random sample of 1955 17-year-olds who were assessed as part of the 1981-1982 national assessment in science. The dependent variable was a 17-item measure of students' inquiry skill. The independent variables were selected from the available data using the Model of Educational Productivity as a guide in the selection of the variables. The first purpose of the study was to test the effectiveness of the Model of Educational Productivity for predicting the inquiry skill of 17-year-olds. The results of this study indicate that this model was capable of accounting for between 24 and 32% of the variance in inquiry skill for the general population of 17-year-olds. More specifically, students' reporting of their general ability alone accounted for between 17 and 22% of the variance. The second question posed by this study asked whether the prediction of inquiry skill differed for males and females. While there was some difference in the contribution of the minor predictors, there was very little difference in the prediction of inquiry skill for males and females using the Model of Education Productivity. The third question posed by this study asked whether the prediction of inquiry skill differed for white and nonwhite students. For nonwhite students, the Model of Educational Productivity accounted for only 18% of the variance in science inquiry skill. Thus, it would appear that there is a great deal that is not known about the factors that contribute to the science inquiry skill of nonwhite students. 相似文献
997.
998.
Herbert H. Severson Marianne Pickett Deborah J. Hetrick 《Psychology in the schools》1985,22(2):179-186
One hundred eighty-one experienced teachers (elementary and junior high), and 189 preservice teachers were surveyed regarding their perceptions of school psychologists. The survey instrument used essentially the same categories as Styles in 1965, including: (a) level of training, (b) effectiveness, (c) qualifications for tasks, and (d) usefulness in specific duties. Analysis of the survey data showed there were significant differences between preservice and experienced teachers' effectiveness ratings of school psychologists on eight tasks typically performed by school psychologists. Significant differences also were found between preservice and experienced teachers on their ratings of school psychologists' qualifications to undertake specific tasks, although almost half of the experienced teachers were unable to rate the effectiveness of school psychologists. There was a small, but significant, negative relationship between the amount of contact with the school psychologist and the perceived effectiveness. Limitations inherent in survey methodology and the need to foster greater teacher awareness of the school psychologist's role are discussed. 相似文献
999.
1000.
Richard J. Gigliotti 《Research in higher education》1987,26(4):401-415
Knowledgeable observers generally agree that students can give reasonably unbiased assessments of their classes, as long as proper instruments and procedures are used. These same observers agree, however, that more research is needed to understand the subtle dynamics which affect evaluations. Students' expectations (obtained on the first day) and the violation of these expectations are two possible factors. Their effects on students' final interest and future intentions are compared with students' actual reports of the class given at the end of the semester (n=196). Regression analysis using a simultaneous entry of expectations, expectancy violations, and final reports shows that students' reports at the end of the course account for almost all of the explained variance in the course rating items. 相似文献