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Douglas S. Grant 《Learning & behavior》1982,10(1):7-14
In two matching-to-sample experiments, pigeons’ performance with samples of stimuli (red and green), number of responses (1 and 20), and reinforcers (food and no food) was assessed. Samples of red, 20 responses, and food were associated with the red comparison stimulus, and samples of green, 1 response, and no food were associated with the green comparison stimulus. On interference trials, three sample types were presented on each trial, and two of the samples (congruent) were associated with the correct comparison and the third sample (incongruent), with the incorrect comparison. Performance on interference trials was compared with that on control trials in which either two (Experiment 1) or three (Experiment 2) congruent samples were presented. It was found that presentation of an incongruent sample reduced matching accuracy markedly, and about equally, whether samples were presented successively or in compound. Although the type of sample that was incongruent was without effect, matching accuracy declined strongly as the recency of the incongruent sample increased. Serial position of the incongruent sample also influenced the shape of the retention function on interference trials. Presentation of the incongruent sample either first or second resulted in accuracy decreasing across the retention interval, whereas presentation of the incongruent sample last in the input sequence resulted in increasing accuracy across the retention interval. The theoretical implications of the findings are considered. 相似文献
203.
Exploring the Effects of Financial Aid on the Gap in Student Dropout Risks by Income Level 总被引:1,自引:0,他引:1
Using national survey data and discrete-time logit modeling, this research seeks to understand whether student aid mediates
the relationship between parental income and student dropout behavior. Our analysis confirms that there is a gap in dropout
rates for low-income students compared with their upper income peers, and suggests that some types of aid are associated with
lower risks of dropout. Thus, we examine the interaction between financial aid type and parental income to explore whether,
and if so how, different types of aid may reduce the dropout gap by income level group. We find that the receipt of a Pell
grant is related to narrowing the dropout gap between students from low- and middle-income groups, although overall the interaction
between Pell grant and income is not significant. Loans and work-study aid both have similar effects on student dropout across
all income groups. Methodologically, our results demonstrate the need to model dropout behavior temporally and to avoid main-effect
bias by incorporating interaction effects.
相似文献
Stephen L. DesJardinsEmail: |
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This article presents a microanalysis of how a group of primary school teachers deals with research evidence in their work. Based on analysis of a group of Norwegian teachers’ interactions over issues of educational research and research-based knowledge, we find that teachers’ representations of educational research particularly center on the following issues: educational research being perceived as circular, ‘polyphonic’, and a matter of accommodation to their experience-based knowledge. These metaphors also shed light upon the dilemmas that arise when research evidence meets teachers’ more contextual knowledge. We conclude that teachers’ practice-based evidence may take new forms with an increased policy focus on research-based evidence, as well as bringing forth challenges for teacher work and professionalism. 相似文献
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This study was conducted to determine if a planning and writing strategy would improve the essay writing of students with learning disabilities. Four participants were taught a strategy designed to facilitate the setting of product and process goals, generation and organization of notes, continued planning during writing, and evaluation of goal attainment. Training effects were investigated using a multiple probe design across subjects. Strategy instruction had a positive effect on students' essay writing performance and knowledge of the writing process, and effects were maintained over time. 相似文献
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