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991.
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
992.
Nancy A. Marlin 《Learning & behavior》1981,9(4):519-523
Rats were given tone-footshock pairings with a 0-, 10-, or 30-sec trace interval between tone offset and shock onset. Half the rats within each trace interval were tested for their conditioned fear of the tone through a lick suppression procedure; the remaining rats were evaluated for their fear of the background or contextual cues through their avoidance of the compartment in which conditioning had occurred. Less conditioning was observed to the tone with increasing trace intervals. However, conditioned fear of the context increased with increases in the trace duration. The ability of the more predictive stimulus, the tone, to overshadow the contextual cues was determined by the tone’s temporal contiguity with the footshock. The need to incorporate temporal parameters within current theories of conditioning is discussed. 相似文献
993.
994.
The study evaluates the effectiveness of an in-service science program through measuring the use of materials available from the school district's resource supply center. This in-service program introduced the Science Curriculum Improvement Study simultaneously into all 35 elementary schools of one district. The live-material shipment orders served as an unobtrusive means of measuring teachers' behaviors. The 168 participants in the workshop before implementation did not significantly differ from the other 361 teachers in their use of materials. These participants were selected on the basis of availability and representation from each school. On a questionnaire they indicated a very high level of satisfaction with the workshop. The 128 participants in a second workshop during the summer following the first year of implementation made significantly greater use of the materials. 相似文献
995.
Educational technology research and development - 相似文献
996.
One of the more astonishing characteristics of educational research is the relative lack of social organizational analyses of higher educational institutions. There is even a greater gap in the literature with regard to thechange process associated with a given university or college. The present study is an examination of one college's attempt to change from a traditional white female finishing college to a larger biracial and coeducational college committed to experimental and innovative educational programs. Two ideal types of educational social organizations are utilized as explicit aids for the specification of the educational change process observed for the Becoming Place during the time period 1969 to 1975. The major findings, which are based on several data sources, can be summarized as follows. (1) Even when a proposed educational change is characterized by ideals of maximum involvement in the decision making process for all members of a college community, resistance to the change can be very substantial. (2) Ironically, little or no involvement by the faculty, students, and alumni in the initial decision to innovate was a major factor for the resistance to educational social change. The research is concluded with a consideration of the findings in terms of possible implications for the future of small colleges.An earlier version of this paper was presented at the annual meeting of the Southern Sociological Society, Knoxville, TN, April 1980. 相似文献
997.
To test how sex biases operate in the screening of candidates for administrative positions, an experimental study was conducted to evaluate the contribution of gender and career pattern effects on candidates' ratings. Faculty from seven universities were asked in a task that was judged to be realistic to evaluate vitae of six candidates for a deanship of a college of arts and sciences. Experimental design permitted alteration of the vitae to change gender and career patterns. No significant difference was found in the ratings assigned to male and female candidates. Career break did have a significant effect; candidates with career breaks received higher ratings on the average than those without career breaks. There was no significant interaction of gender and career break. Three different ratings systems were used, but none interacted with either gender or career break. However, closer examination of screeners' ratings did suggest that career experience was evaluated in different ways for male and female candidates. 相似文献
998.
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
999.
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
1000.