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971.
972.
Sequence learning in pigeons was studied in asimultaneous chaining paradigm: all stimuli and the opportunity to respond to each stimulus were available simultaneously. In contrast to the traditionalsuccessive chaining paradigm, a simultaneous chaining paradigm provides no differential feedback following each response (except the last). Subjects were first trained to perform on sequences of two (AB), then three (ABC), and then four colors (ABCD). Performance greatly exceeded that predicted by models of random choice. Generalization to novel arrays of three and four colors was complete. After training with a four-color sequence, the subjects were tested with subsequences consisting of all possible combinations of two and three of the four training colors (e.g., BD, AD, BC, ACD, BCD, etc.). The successful completion of these subsequences showed that the organization of the original sequence did not entail overt pecks to successive elements of that sequence. That subjects can respond accurately on nonadjacent subsets is not readily explained by a chaining theory, or by any theory that assumes that responding to element n provides a cue for responding to element n+1.  相似文献   
973.
Educational technology research and development -  相似文献   
974.
The purpose of this review was to synthesize the research on the relationship between performance on Piagetian tasks of concrete operations and performance on mathematics learning tasks in order to determine whether the Piagetian tasks make useful readiness measures. The research consistently indicates that, while there is a positive correlation between performance on Piagetian tasks and mathematics achievement, many school mathematics tasks can be mastered by children who have not yet developed the reasoning abilities measured by Piagetian tasks. This does not diminish the validity of Piaget's theory, but rather suggests that the kinds of reasoning processes identified by Piaget are not essential in solving many school mathematics tasks.  相似文献   
975.
Financial problems at colleges and universities have led many institutions to initiate extra efforts to obtain extramural funds. One such effort has been the establishment of formula-based research incentive plans. These plans generally utilize the recovery of indirect costs as the basis for allocating additional incentive funds to various areas as an encouragement to obtain additional extramural funds. Data from surveys conducted by the University of Missouri-Kansas City and Ohio University were combined with National Science Foundation reports to provide information about this relatively recent phenomena. The increasing popularity of these plans was shown in that a majority of institutions had such plans in effect during FY 1979. Analyses of the effectiveness of these plans showed no statistically significant differences between institutions with incentive plans and those without such plans, although mean federal research expenditures were approximately 20% greater at those institutions without these incentive plans. The evidence presented indicates that the receipt of federal research funds is not associated with the use of a formula-based research incentive plan.  相似文献   
976.
977.
Three experiments with rat subjects were designed to investigate the possibility that an extinguished saccharin aversion might be reinstated if the animals are made ill with lithium chloride (in the absence of saccharin) following extinction. Although reinstatement can be obtained when the unconditioned stimulus is presented following the extinction of other kinds of conditioned behaviors, the present experiments provided no evidence that an extinguished taste aversion can be reinstated. No reinstatement was observed, even when the aversion had been only partially extinguished and when multiple injections of lithium chloride were administered in an attempt to reinstate the aversion.  相似文献   
978.
We have undertaken a critical appraisal of the current English system of law regulating: (1) Provision of services designed to prevent children coming into care of local authorities, which are the authorised agencies for dealing with children who are abused or neglected. (2) Ways of receiving children into care and also ways of terminating care orders. We question whether, and under what circumstances, care orders are really necessary. (3) Periodic reviews of children in care. We are critical of the English system and look to models in the USA as guides towards the possible reform of English law. We take the same perspective when considering termination of parental rights. In our opinion good laws do not of themselves provide the care and love which a child requires, but they make the caring possible by loved and loving adults. We argue that the law must provide the best possible framework to allow adequate caring by members of the non-legal professions, such as social workers and foster parents. At the same time the law must ensure that the rights of parents and children are protected.  相似文献   
979.
980.
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