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101.
The misgivings of college faculty, college administrators, and high school counselors about selective admissions are focused on 9 issues. Data relevant to those issues reveal that: (1) prediction of grades is sufficiently accurate to be useful; (2) prediction equations from one year are sound for use in the immediately succeeding years; (3) predictions of first-year grades are related to performance over the 2-year period at a junior college and the 4-year career at a senior college; (4) there may need to be separate prediction procedures for widely different majors, such as science and nonscience; (5) accurate predictions can be made before the student has completed high school; (6) the nonacademic courses students take do not reduce prediction accuracy; (7) introduction of selectivity has not been found to decrease diversity in educational opportunity; (8) grading practices in an institution will tend to fluctuate with the degree of selectivity; and (9) procedures are available to set admissions cutoffs, to provide students with sound counseling information, and to provide a second chance for those who do net meet minimum admissions standards.  相似文献   
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Reaction time (RT) to the second of two stimuli presented in rapid succession was examined as a function of the intensity of the first stimulus (S1). It was found that the delay in RT2 was greater following a dim first stimulus than following a bright first stimulus. The magnitude of this increase corresponded to the difference in RTs to the two intensity levels of S1. These results support the prediction of a single channel model of response selection. Examination of mean first RTs revealed a general elevation in latency of RT. However, since this increase was not influenced by the inter-stimulus interval (ISI) or by the intensity of the second stimulus (S2), and since the same increase was found on “catch trials“ where no S2 was presented, this increase is considered to be a function of change in set in the double response situation.  相似文献   
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Magnetic resonance imaging is a promising technological advance used for research and diagnosis of disease. The procedure has no risks, except when uncooperative patients require sedation. Four normal children participated in simulated scans to study the effects of (a) antecedent changes in the imaging environment and (b) operant conditioning of movement inhibition. Changing the environment can decrease movement, but operant contingencies were necessary to decrease movement to a level that, in most cases, would allow the procedure to occur without sedation.  相似文献   
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We compared suicide attempts, depressed mood, and drug use of 1,710 Dominican public high school students in New York City (NYC) and 9,573 in the Dominican Republic (DR) in 2009. Compared to DR Dominicans, NYC Dominicans were more likely to have reported lifetime marijuana use (27.6% vs. 1.5%), lifetime inhalant use (11.0% vs. 7.6%), lifetime other drug use (9.9% vs. 3.0%), depressed mood (31.3% vs. 27.2%), and suicide attempt (13.8% vs. 8.8%). The results of this study supported the hypothesis that substantial increases in illicit drug use, especially cocaine, heroin, ecstasy, and methamphetamines, among NYC Dominican youth account for their increased risk for suicide attempts compared to their DR Dominican counterparts. It also identified suicide attempts as a public health problem among NYC Dominicans, the largest NYC Latino immigrant population.  相似文献   
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The objective of this study was to identify factors associated with complete mental health among Canadians who had ever seriously considered suicide. Data for this study were obtained from Statistics Canada's 2012 Canadian Community Health Survey–Mental Health (N = 2,844). The outcome variable examined in this study was complete mental health and was analyzed using binary logistic regression. Of the 2,844 respondents with lifetime suicidal ideation, 1,088 (38.2%) had complete mental health (i.e., had flourishing mental health, no mental illness, and no suicidal ideation in the past 12 months). Those who had a confidant were seven times more likely to have complete mental health. Other factors associated with achieving complete mental health among formerly suicidal respondents include being older, being a woman, having higher income, use of religious coping, and never previously having a mental illness. Considering the importance of these protective factors in formulating public health policies will allow for a more wide‐reaching approach to suicide prevention.  相似文献   
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