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921.
In a direct comparison, flavor-cued rats learned to avoid shock in a two-way shuttlebox as well as, or better than, tone-cued rats. These results stand in contrast to the prevalent view that rats encounter difficulty in forming flavor-shock, but not tone-shock, associations. In attempting to account for this contrast, we note that experiments revealing cue-modality specificity employ an aversion paradigm and record ingestive behavior. It is argued that both the paradigm and the dependent variable are inappropriate for assessing shock-avoidance learning, and that cue-modality specificity in such a setting reflects paradigm and response choice rather than a general characteristic of rats. 相似文献
922.
ABSTRACTEducators in higher education commonly use peer and self evaluations to help assess student performance on group projects. Although these evaluations provide multiple benefits, many educators are wary of using them due to concerns about their quality. This study addresses three questions debated in the literature regarding the quality of these assessments. How much do students differentiate among peer contributions through their ratings? How reliable are peer ratings? How much agreement exists between peer and self ratings? Although these questions have been addressed to varying degrees in past work, their answers have been far from settled. While many studies focus on just one of the questions, this study’s data make it possible to address all three questions for the same group of students as well as examine each question by student performance level. The evaluations assessed in this study were completed by a large number of students under conditions associated with obtaining more valid and reliable ratings. Overall, the results provide support for using peer and self evaluations to help assess student contributions to group projects. Peer ratings were largely reliable as group members generally agreed on the scores given to their peers. In addition, most students differentiated among group member contributions through their ratings. Students also tended to rate themselves higher than their peers rated them. This study has implications for how peer and self evaluations can be most effectively used by educators to measure student performance in group work. 相似文献
923.
924.
925.
This paper examines the propensity to attain a Ph.D. degree at the five largest universities in Flanders, the Dutch speaking
part of Belgium. It provides insight into the rate at which junior scholars appointed at the universities involved attained
their Ph.D.-degree, and the duration of the doctoral training period. Cox’s regression model was applied to statistically
analyse the influence of a number of ‘demographic’ and ‘merit’ variables, and variables related to funding source and type
of appointment of the junior scholarly staff. Large differences in Ph.D. durations and attainment rates were found across
funding sources, research disciplines and types of appointments. The policy background and implications are discussed briefly. 相似文献
926.
F. David Boulanger 《科学教学研究杂志》1981,18(4):311-327
The purpose of this study was to quantitatively synthesize quality and quantity of instruction studies with the same or similar independent variables in the published science education grade 6-12 research of the 1963-1978 period. Fifty-two studies formed six clusters and revealed significant positive cognitive outcomes due to the use of preinstructional strategies, training in scientific thinking, increased structure in the verbal content of materials, and increased realism or concreteness in adjunct materials. In general, systematic innovation in instruction was found to produce positive improvements over the norm or traditional practice. Methodologically, improved research design quality was related to larger effect sizes. Recommendations are made regarding application, use of multiple measures, attitudinal research, use of general education findings, and the reporting of research. 相似文献
927.
Summary This study was designed to test the hypothesis that group orientated classroom management procedures may achieve their apparent success merely by raising still further the on‐task behaviour of non‐troublesome pupils. To this end, 1812‐13 year old pupils in a secondary school remedial class were observed and their individual levels of on‐task behaviour recorded. The class teacher's use of approval and disapproval was also noted.
Following the collection of baseline data, a modified, simple ‘rules, praise and ignoring’ intervention strategy was implemented, followed by a partial reversal to baseline conditions. Mean class on‐task behaviour was clearly shown to increase from 77% at baseline to 91% during intervention and this was maintained during the partial reversal. Moreover, it was shown that every pupil's on‐task behaviour increased, these increases varying between 3 and 33%, the pupils with the lowest baseline levels making the biggest gains. 相似文献
928.
The instructional development (id) process sometimes is perceived as being too time-intensive and as delaying instructional materials development. Course writers
holding these perceptions may resist following a formalid process or give only cursory attention to early stages in the process. Such a situation can create conflict between course
writers and instructional designers responsible for implementing a particularid model. This article describes a way instructional designers can overcome some of the resistance to following theid process. 相似文献
929.
Whereas rats exposed to a series of progressively decreasing shock durations show deficits in shuttle-escape performance 24 h later, the same number and intensity of shocks in the reverse (increasing) order of durations does not produce the “learned helplessness” effect (Balleine & Job, 1991). We conducted two experiments to establish the generality of this shock-duration order effect on other measures of distress and helplessness in rats. In Experiment 1, rats exposed to decreasing durations of inescapable shock showed reduced consumption of quinine-adulterated water (finickiness), whereas increasing durations produced no finickiness. By contrast, increasing shock durations produced greater conditioned fear to the shock context than did decreasing shock durations in Experiment 2. The differential effects of shock-duration order on finickiness and fear are explicated in terms of the specificity of fear conditioning during exposure to increasing versus decreasing series of shock duration orders. 相似文献
930.