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81.
The purpose of this study was to develop and validate instruments that will assess the laboratory skills of students completing high school science courses. In each of the science areas (biology, chemistry, and physics), tests were developed around six laboratory tasks. Each test used a two-part format with a total time of 80 minutes. Students had to plan an investigation, collect and organize appropriate data, and formulate conclusions based on calculations and graphs. A different test was developed for 12th-grade students not enrolled in a science course. This test consisted of a series of stations where students conducted a short activity that was presented to them. Over 1000 students from 32 Ohio schools formed the sample for this study. Data are presented by skill and by task. In addition, analysis for gender and school effects is included. 相似文献
82.
Early mother-infant interaction and later security of attachment were assessed for 17 pairs of twins, 5 singleton survivors of twin pairs, and 20 singletons, all low-birth-weight preterm infants. Mother and infant behavior during home observations at 6 weeks and 3, 6, and 9 months was rated on scales developed by Ainsworth and Egeland and Brunquell. A, B, and C patterns of behavior in the Strange Situation conformed to the frequencies predicted from prior full-term samples and were not affected by twinship. However, the proportion of B1 and B4 dyads in the B group significantly exceeded that predicted from normative data. Mothers in B2 and B3 dyads were rated more sensitive and responsive than all others at all 4 observations. Contrary to our expectations that mothers in A and C dyads would receive the lowest ratings, this occurred only at 6 weeks. At later observations mothers in B1 and B4 dyads consistently received the lowest ratings. The discussion focuses on possible reasons for this unexpected finding. 相似文献
83.
Rats lived continuously in an operant chamber in which they were able to press a bar to obtain food on a chained FR50:CRF schedule that allowed them control of both the size and frequency of individual meals. Independent groups of animals were scheduled to receive 12, 24, 48, or 96 electric shocks per day, which were given randomly in time and independent of the subjects’ behavior. Rats could avoid shock by remaining in a safe area of the chamber, but they were always at risk while barpressing. The introduction of shock resulted in a number of changes in feeding patterns. In rats exposed to a possible 12 shocks/day, meal size increased whereas meal frequency changed very little. At 24 shocks/day, meal frequency decreased whereas meal size increased such that net intake remained stable relative to a preshock baseline period. As shock density was increased to 48 or 96 shocks/day, total intake was suppressed. At 96 shocks/day, both meal frequency and meal size decreased dramatically. Shock-related changes were also observed in rates of operant responding and in the amount of time the animals engaged in feeding-related behavior. All of the animals were able to achieve a greater than 50% reduction in the total number of shocks received relative to equivalent random samples of their position in the apparatus taken during baseline. These results support the position that the nature of defensive changes in feeding behavior that are seen when an aversive stimulus is introduced: into a simulated foraging situation varies as a function of risk. 相似文献
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The study consisted of 25 full-time Electronic Technician Certificate students with 16 randomly assigned to an experimental group registered in a team-taught learning community and with nine randomly assigned to a control group registered for individually taught unlinked classes. We hypothesized that the experimental group would have significantly better academic and social integration and more positive perceptions of their experiences than the control class as well as higher course grades and grade point averages, more contact with classmates and instructors, and greater commitment to college and second semester persistence. Both student self-reported surveys and institutional data were analyzed. Results indicated that the team-taught learning community did make a difference to its students and yielded quantitative and qualitative support for hypotheses dealing with student perceptions of academic and social integration. Findings failed to support hypotheses dealing with behavioral outcomes except for strong support for commitment to college. 相似文献
87.
Three substudies of effects of different formats on student ratings of faculty teaching effectiveness were conducted. One substudy, Kinds of Keys, investigated three main kinds of keys: Agreement, Evaluation, and Needs Improvement. The second, NO TUP, investigated numbers of positive rating categories. The third, Item Wording Direction, investigated the same items worded positively, negatively, and neutrally, respectively. Practically important differences in level of ratings obtained in Kinds of Keys and practically and statistically significant differences obtained in NO TUP and Item Wording Direction. It was concluded that additional research is necessary to determine if apparent differences in teaching effectiveness are actually differences in teaching effectiveness or differences due to the methods of measurement. 相似文献
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Salden Ron J.C.M. Paas Fred Broers Nick J. van Merriënboer Jeroen J.G. 《Instructional Science》2004,32(1-2):153-172
The differential effects of four task selectionmethods on training efficiency and transfer incomputer-based training for Air Traffic Controlwere investigated. A non-dynamic condition, inwhich the learning tasks were presented to theparticipants in a fixed, predeterminedsequence, was compared to three dynamicconditions, in which learning tasks wereselected on the basis of performance, mentaleffort, and a combination of both (i.e., mentalefficiency). Using the 3-factor mentalefficiency formula of Tuovinen and Paas (2004, this issue), the hypothesis that dynamic taskselection leads to more efficient training thannon-dynamic task selection was confirmed.However, the hypothesis that dynamic taskselection based on mental efficiency leads tomore efficient training than dynamic taskselection based on performance or mental effortalone was not supported. The results arediscussed in light of the theoretical frameworkand suggestions are given for futureresearch. 相似文献