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221.
In Experiment 1, male rats were exposed to either aggressive (i.e., alpha) or nonaggressive conspecific colonies and tested 24 h later, with or without alpha odors, for freezing behavior and burying of a wall prod that had been the source of a brief electric shock. The results indicated that prior defeat experience and the presence of alpha odors alone during testing had no significant effects, but the combination of prior defeat and alpha-odor testing significantly decreased burying and increased freezing behavior. In Experiment 2, we examined the effects of noncontact exposure to a cat, as a predatory Stressor, during subsequent prod-shock tests involving the presence or absence of cat odors. Exposure to a cat failed to disrupt later prod burying and did not produce freezing. However, the presence of cat odors during testing significantly reduced the amount of defensive burying,without resulting in an increment in freezing. In Experiment 3, rats were given 1, 5, or 30 inescapable preshocks in the presence of either cat odors or a hedonically neutral citronella odor and were tested 24 h later for prod burying and freezing with or without these odors. Both the cat and the citronella odors resulted in a significant reduction in burying and an increase in freezing for rats given 5 and 30 preshocks and tested in the presence of these respective conditioned odors. For the groups that were given 5 preshocks, preshock and later testing in the presence of cat odors resulted in significantly less prod burying and more freezing than for rats that were preshocked and tested in the presence of citronella. The findings of these three ethoexperimental studies are discussed in terms of the learned-helplessness theory, the stress-coping-fear-defense (SCFD) theory, and the concept of selective CS-US associability. 相似文献
222.
Institutional administrators, faculty, state planners, and legislatures have little analytical basis available to help them cope with the expected excess higher education capacity of the 1980s. Without objective criteria, state planners and legislatures are likely to propose across-the-board reductions even if it were preferable to close some institutions and expand others. This study is a case application of an optimization model to two community colleges in northern Minnesota. Using estimated enrollment demand functions and readily available data on size, quality, and costs, this model is designed to assist policymakers in identifying overbuilt institutions and programs that should be closed. The state's objective in the model is to satisfy specified proportions of enrollment demand with a minimum expenditure of state funds. 相似文献
223.
224.
Tamara van Gog K. Anders Ericsson Remy M. J. P. Rikers Fred Paas 《Educational technology research and development : ETR & D》2005,53(3):73-81
Cognitive load theory (CLT) has been successful in identifying instructional formats that are more effective and efficient
than conventional problem solving in the initial, novice phase of skill acquisition. However, recent findings regarding the
“expertise reversal effect” have begun to stimulate cognitive load theorists to broaden their horizon to the question of how
instructional design should be altered as a learner's knowledge increases. To answer this question, it is important to understand
how expertise is acquired and what fosters its development. Expert performance research, and, in particular, the theoretical
framework of deliberate practice have given us a better understanding of the principles and activities that are essential
in order to excel in a domain. This article explores how these activities and principles can be used to design instructional
formats based on CLT for higher levels of skills mastery. The value of these formats for e-learning environments in which
learning tasks can be adaptively selected on the basis of online assessments of the learner's level of expertise is discussed.
In their preparation of this article, the first and last authors were supported by an Internationalization grant from the
Netherlands Organization for Scientific Research (NWO, The Hague, project number 411-01-010). 相似文献
225.
This study examined the effects of rewards on the ideational fluency of 75 preschool children. Assigned to a reward or nonreward condition, the children were administered two ideational fluency tasks, Unusual Uses and Pattern Meanings. Analyses revealed a significant main effect for reward on the ideational fluency components of originality, total fluency, and flexibility. In all cases the rewarded subjects scored lower than the nonrewarded group. These findings support the growing body of evidence that rewards are detrimental to creative functioning. 相似文献
226.
Putten Jim Vander McLendon Michael K. Peterson Marvin W. 《Research in higher education》1997,38(1):131-149
Evidence of substantial growth in unionization among university noninstructional staff over the past 20 years (Hurd and Woodhead, 1987) and the emergence of a quality movement in higher education linking employee attitudes toward the work environment with increased productivity point to the need for additional research into union and nonunion staff perceptions of the work environment. This paper describes a conceptually oriented, exploratory study of the university work environment as perceived and defined by union and nonunion noninstructional staff. 相似文献
227.
K. Patricia Cross 《高等教育研究与发展》1987,6(2):99-108
The role of higher education has changed in the United States. It has become a learning society where egalitarian pressures for equal opportunities led to the expansion of educational services to broader and more representative segments of society. Five propositions illustrate the current pressures for change. (1) Institutions of higher education no longer enjoy a monopoly on the provision of educational services. The learning society has given higher education new competition for the growing adult market. (2) The roles of education providers are increasingly blurred. (3) Higher education no longer has the full‐time commitment of students or of faculty. (4) Lifelong learning has become a lifelong necessity for almost everyone, which demands flexibility and responsiveness to change on the part of higher education. (5) A change is needed in the methods of teaching and learning to accommodate adult learners and to provide for the long‐ range needs of the learning society. 相似文献
228.
229.
RONALD K. HAMBLETON DENNIS M. ROBERTS ROSS E. TRAUB 《Journal of Educational Measurement》1970,7(2):75-82
Differential weighting of response alternatives and confidence testing have been proposed as ways to assess partial knowledge on multiple-choice tests. 211 students in an educational measurement course took their midterm examination under one of three procedures. Results from those students administered the test under conventional directions provided a baseline for comparing, in terms of reliability and validity, the results from students who took the test under the differential weighting of response alternatives or the confidence testing instructions. Reliability was estimated by the split-half technique. Validity was estimated by correlating midterm test scores with scores on a final examination. This investigation provides some support for the contention that validity can be improved using more sophisticated testing techniques. Suggestions for the conduct of more definitive studies were offered. 相似文献
230.