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101.
While the “achievement gap” generally and appropriately focuses upon gaps in test scores and other outcome measures, there may also be an “information gap” between higher and lower income parents that creates a disadvantage for lower income families in choosing good schools. In this article, we examine the extent to which there is such a gap, with a focus on data from a new survey of low‐ and moderate‐income parents who have made school choices. We find that, at least in relatively mature school choice environments like Milwaukee, Wisconsin, and Washington, DC, most low‐ and moderate‐income parents report being quite well informed and they engage in a variety of different activities to become informed. Thus, the information gap between lower and higher income parents may not be as large as scholars and policymakers had assumed. We do find that parents at the very lowest end of the income spectrum, especially those earning less than $10,000 per year, do feel less well‐informed and gather less information, but even here the differences are not enormous, relative to higher income parents.  相似文献   
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He directs longitudinal studies designed to test general models of deviant adaptations to stress. A past editor of the Journal of Health and Social Behavior,his recent publications include “Self-Rejection and the Explanation of Deviance,” “Escalation of Marijuana Use,” and “The Sociological Study of AIDS”; as well as Social Psychology of Self-Referent Behavior, Patterns of Juvenile Delinquency,and Psychosocial Stress.  相似文献   
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In this summary of fertility literature the author attempts to differentiate between the effects of behavioral and medical models of family planning programs on the fertility rate. This is done by determining the effects of access to social welfare services by assessment of: the function of children within the family life survey conducted in the Cameroons are also used. It was found that 7 interdependent elements of social service are involved: 1) general health care; 2) social security for sick and aged; 3) employment training and opportunities for adults; 4) literacy and education; 5) communication and transportation systems; 6) housing and infrastructure; 7) child care and welfare. The presence of these elements is shown to accompany low fertility while their absence is expressed in high rates of child bearing. These elements are major variables in both the nomological and public policy senses. 2 additional components are knowledge of and favorable attitudes towards effective means of fertility control plus effective mechanical, chemical, or natural means of limiting fertility. The concept of fertility norm and its impact on the fertility rate is explained as being the result of the collective force which social affiliations exert on people to reproduce in a certain way. The "stopping rule" is that which will fulfill the fertility norm. An example of this is a culture which continues child bearing until a son has been born and then controls reproduction after this has happened. Such factors must be considered for family planning programs to succeed in these cultures. Therefore fertility levels are found to be the product of prevailing norms and technical ability to achieve these norms. Improvement in levels of access to social services can bring about the lowering of these norms.  相似文献   
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High-risk Mexican American males were assessed for levels of psychopathy. The Hare Psychopathy Checklist-Screening Version was compared in a random sample of gang members with a matched community sample of violent non-gang members and samples of forensic and psychiatric patients and undergraduate students. Analysis involved t-test, chi-square, and Cronbach's alpha statistics. More than half of the gang sample were categorized as low, 44% as moderate, and only 4% as high on psychopathy. The gang members had higher scores on the total, affective, and behavioral scores than the non-gang members. High scores on adolescent antisocial behavior, poor behavioral controls, and lack of remorse were found in both samples. Gang members scored twice as high as non-gang members on lack of empathy. Both samples were lower on psychopathy than the forensics and higher than psychiatric patients and undergraduates. The results provide grounds for early intervention efforts for this high-risk population.  相似文献   
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The efficiency of conventional polarized light microscopy (PLM) methods for analyzing synthetic fiber evidence analyses is improved. Historically, using PLM for fiber identification relied on measuring refractive index. This prior PLM technology is reliable, but it is not efficient. Most fibers are optically anisotropic, having two principal refractive index values, N(High) and N(Low). When the fiber is mounted in intermediate refractive index medium, efficiency is improved by observing the change in contrast while the polarized light’s vector is rotated relative to the fiber’s axis. Minimum contrast occurs when the refractive indices of the mounting medium and fiber are equal. This angle of equality is determined by orienting the fiber’s highest refractive index parallel to the polarized light’s electric field vector, rotating the fiber or polarizing element, observing minimum contrast and measuring the angle of equality. This method is rapid, reduces remounting fibers in different mounting media and provides a quantitative measure for fiber comparisons.  相似文献   
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