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151.
Abstract

This research evaluates the impact of family structure on the educational attainment of northern urban blacks. Separate analyses of male and female adults reveal little support for the traditional view that the “broken home” lowers the achievement of black males. Rather, we find it is black females, especially in segregated contexts, who have been most adversely affected by parental absence. These findings are interpreted as reflecting the different relationship of males and females to the family under conditions of structurally-induced poverty.  相似文献   
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There is a large literature suggesting that “WIC works” to improve birth outcomes. However, methodological limitations related to selection into the Women, Infants, and Children (WIC) program have left room for doubt about this conclusion. This article uses birth records from New York City to address some limitations of the previous literature. We estimate models with mother fixed effects to control for fixed characteristics of mothers and we directly investigate the way that time‐varying characteristics of mothers affect selection into the WIC program. We find that WIC is associated with reductions in low birth weight, even among full‐term infants, and with reductions in the probability that a child is “small for dates.” These improvements are associated with a reduction in the probability that the mother gained too little weight during pregnancy. Improvements tend to be largest for first born children. We also find that women on WIC are more likely to be diagnosed with chronic conditions, and receive more intensive medical services, a finding that may reflect improved access to medical care. (JEL I12, H42)  相似文献   
156.
Since the early 1950s, the National Heart, Lung, and Blood Institute (NHBLI) has conducted a long series of influential randomized clinical trials in heart, lung, and blood diseases. The biostatisticians at the Institute have been central to the design, conduct, monitoring, and final analyses of these trials. The uniquely favorable deck of cards the group of biostatisticians at the Institute has been dealt over the six and half decades of the group's life has led to contributions that have had a major impact on the fields of biostatistics and clinical trials. The leaders of the NHLBI and its several Divisions have valued the independence, creativity, and collaborative interactions of statisticians within the Institute. The medical problems the Institute faced impelled the statisticians to develop methodology that would address questions of great public importance. Perhaps most importantly, the individual members of the group had a collective vision passed from member to member over time that new methodology must fit the questions being asked. The group has always had the technical ability to develop new methods and the conviction that they were responsible for ensuring that they could explain their methods to the clinicians with whom they worked.  相似文献   
157.
Over the last 20+ years, globalization has made international trade and investment more efficient and productive. In the absence of coordinated global regulatory regimes, it has also made multinational corporations (MNCs) impervious to social concerns in the countries where they operate. There is considerable debate in the academic, political, and business arena as to the causes of the apparently inequitable distribution of benefits between labor and capital. Notwithstanding, the relative merits of this debate, and facing tremendous societal pressure, companies have adopted voluntary codes of conduct to ensure that workers making products for them in poor and developing countries are protected from hazardous working conditions and receive wages that meet local laws and market conditions. These codes, however, suffer from a lack of credibility and proof of substantive compliance. A new type of nongovernmental organization (NGO) has emerged that monitors a company's compliance with prespecified standards and provides assurance to the external stakeholders that the company has fulfilled its voluntary obligations. From an historical perspective, this has been an innovative phenomenon where the monitoring organization purports to act as an honest broker to ensure all concerned that the company/industry has fulfilled its obligations. In this article, we undertake a thorough examination of two such organizations, that is, Fair Labor Association, and Social Accountability International, that have played a pioneering role in bridging the gap between societal expectations and corporate performance. We examine their governance structures, operating procedures, monitoring standards, and public disclosure of findings, and above all, their success in improving the level of corporate compliance with their self‐created codes or standards. Unfortunately, our findings and conclusions are disappointing. In our view, the two groups have mostly failed to meet their avowed goals. Rather than using their NGO status to help companies improve their code compliance, they have suffered from managerial capture and have been reduced to corporate apologists.  相似文献   
158.
Objective To compare gambling behaviors in a random sample of community residents with and without mental disorders identified by the Composite International Diagnostic Interview (CIDI).Method A large national community survey conducted by Statistics Canada included questions about problems arising from gambling activities as per the Canadian Problem Gambling Index (CPGI). We compared respondents within three gambling severity categories (non-problem, low severity and moderate/high severity gambling) across three diagnostic groupings (mood/anxiety disorders, substance dependence/harmful alcohol use, no selected psychiatric disorder).Results Of the 14,934 respondents age 18–64 years who engaged in at least one type of gambling activity in the previous 12 months, 5.8% fell in the low severity gambling category while 2.9% fell in the moderate/high severity category. Females accounted for 51.7% of the sample. The risk of moderate/high severity gambling was 1.7 times higher in persons with mood or anxiety disorder compared to persons with no selected disorder. For persons with substance dependence or harmful alcohol use, the risk of moderate/high severity gambling was 2.9 times higher. Persons with both mood/anxiety and substance/alcohol disorders were five times more likely to be moderate/high severity gamblers. The odds ratio for females was 0.6 and for those with less than post-secondary education it was 1.52. Differences in age and personal income were not significant.Conclusions Individuals in the community suffering from mood/anxiety disorders and substance dependence/harmful alcohol, and especially those with both, experience a higher risk for gambling problems. The treatment of these comorbidities should be integrated into any problem gambling treatment program.Disclaimer: The data upon which of the analyses contained in this paper derive from surveys conducted by Statistics Canada. The opinions expressed in this paper do not represent the opinions of Statistics Canada.  相似文献   
159.
Infant phonetic perception reorganizes in accordance with the native language by 10 months of age. One mechanism that may underlie this perceptual change is distributional learning, a statistical analysis of the distributional frequency of speech sounds. Previous distributional learning studies have tested infants of 6–8 months, an age at which native phonetic categories have not yet developed. Here, three experiments test infants of 10 months to help illuminate perceptual ability following perceptual reorganization. English‐learning infants did not change discrimination in response to nonnative speech sound distributions from either a voicing distinction (Experiment 1) or a place‐of‐articulation distinction (Experiment 2). In Experiment 3, familiarization to the place‐of‐articulation distinction was doubled to increase the amount of exposure, and in this case infants began discriminating the sounds. These results extend the processes of distributional learning to a new phonetic contrast, and reveal that at 10 months of age, distributional phonetic learning remains effective, but is more difficult than before perceptual reorganization.  相似文献   
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