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171.
In Grutter vs. Bollinger, the U.S. Supreme Court ruled that the use of race as one factor, among many in admissions decisions is constitutional. It is not known, however, whether future legal opinions will continue to uphold the use of affirmative action policies. Some have argued that class-based preferences can achieve many of the same goals as in affirmative action while being more likely to withstand legal challenges. To date, no empirical studies have been conducted on the potential impact of a class-based admissions policy if implemented at an undergraduate institution. This paper reports on a study at a selective public college and compares a number of outcomes under three admissions models: the original admissions decisions, a purely academic model, and an socio-economic status (SES)-based model. The findings showed that use of the SES-based model would have led to a more academically qualified class than in the original admitted class while maintaining substantially greater student diversity that was found under the academic model. An admissions policy based on preferences for socio-economically disadvantaged applicants appears to hold promise for other colleges and universities with similar institutional and applicant characteristics. The ideas and research design reported in this paper are based on the doctoral dissertation study of the second author, Undergraduate Admissions Models Incorporating Socioeconomic Factors (Johnson, 2000). 相似文献
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Kamin’s three-stage blocking paradigm was investigated in rabbit eyelid conditioning, Two manipulations were examined. A change in the CS-US interval from Stage 1 to Stage 2 did not attenuate blocking. The introduction of a salient stimulus during the intertriai interval in Stage 2 also failed to attenuate blocking. The first result is not consistent with Kamin’s interpretation of the blocking effect in terms of US surprisingness. The second resuit is inconsistent with a prediction based on the Rescorla-Wagner model. 相似文献
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Improving quality of the child care environment through a consultancy programme for centre directors
Katrien O. W. Helmerhorst Ruben G. Fukkink J. Marianne A. Riksen-Walraven Mirjam J. J. M. Gevers Deynoot-Schaub Louis W. C. Tavecchio 《International Journal of Early Years Education》2017,25(4):361-378
This study examined the effects of a newly developed on-site consultancy programme to improve global quality of the child care environment in non-parental child care centres for 0- to 4-year-old children as measured with the ITERS-R/ECERS-R. Using a randomised controlled trial with a pretest, posttest, and follow-up test, we compared 35 experimental group with 33 control group. The consultancy programme comprised three consultations in total. Analysis on the items that were specifically targeted during the consultancy showed a significant improvement on these targeted items between pretest and posttest and between posttest and follow-up. The effect of the consultancy programme on the total scores (including the non-targeted items) was not significant. 相似文献
179.
Robert W. Powell 《Learning & behavior》1974,2(3):185-188
Neither domesticated hooded rats nor wild black rats responded appreciably for water on a CRF schedule when free water was available. However, four out of five crows showed substantial responding for food in the presence of identical free food. Previous reports also indicate that type of reinforcer and species are variables which significantly influence this phenomenon. Nevertheless, the overall findings seem to be amenable to an explanation based upon incentive-motivation theory. 相似文献
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