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51.
Abstract Nonmetropolitan (nonmetro) inequality patterns are contrasted with those of metropolitan (metro) areas to assess the utility of neoclassical and restructuring theoretical frameworks. Inequality measures are constructed from March Current Population Surveys for the years 1968–1991. Results indicate that inequality is greater in nonmetro areas than in metro areas. Results of decomposition procedures suggest that the observed inequality is due to a mix of neoclassical and restructuring factors that account for more inequality in metro than nonmetro areas. National policies must take account of metro/nonmetro differences in patterns and sources of inequality.  相似文献   
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We present and justify a propagation algorithm to facilitate the simultaneous calculation, for every node in a probabilistic exper system of the distribution of the associated random quantity, conditional on all the evidence obtained about the remaining nodes.  相似文献   
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The more things change, the worse they get.Presented April 18, 1991, Duke University, at the Department of Psychiatry's Grand Rounds, this paper condenses, integrates and updates the author's earlier publication. Acknowledgement and thanks for funding and professional sponsorship of the four research studies this paper draws from are selectively due to the Eugene and Agnes E. Meyer Foundation, the Edgar Stern Family Fund, The National Institute for Mental Health, the Baltimore-Washington Institute for Psychoanalysis and the Department of Psychiatry, Children's Hospital National Medical Center.  相似文献   
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Firms facing research costs and demand uncertainty may engage in second-sourcing, in which potential suppliers agree to pool production facilities. I show how sellers and buyers both can benefit from the practice. Second-sourcing allows firms to meet a wider range of possible rates of demand and often to supply a given rate of demand at a lower total cost than under non-cooperation. Buyers benefit through a reduced probability of stock-outs and frequently a lower purchase price. Semiconductor industry data are found to be consistent with the paper's predictions.  相似文献   
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This paper is concerned with how standard estimation procedures perform in terms of eficiency for non-normal rounded data. Previous research has shown that the loss in eficiency due to rounding normal data is small. However, evidence from the non-normal distribution considered in this paper suggests, if rounding is coarse or the distribution is very skewed the loss in efficiency due to rounding can be considerable.  相似文献   
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Primary care physicians are well situated to identify patients with substance abuse problems and motivate them to seek appropriate assistance, but active programs are the exception. A study in a community setting was undertaken to assess the CAGE (the first letters of key words in a series of four questions about drinking: cut down; annoyed; guilty; and eye-opener), instrument in the routine screening for alcohol problems in both new and established patients. The screening process identified subjects for a pilot evaluation of a motivational interview designed to encourage problem-solving behavior. This article focuses on the screening results and the use of the CAGE instrument. During June and July of 1990, 687 patients of two primary care physicians belonging to a large group practice were asked to complete a health questionnaire that included the CAGE. Those who responded affirmatively to at least two of the four CAGE questions were requested to participate in follow-up assessment of problems associated with alcohol and health. The type and severity of alcohol problems experienced by patients who scored positive on the CAGE are described. Prevalence of a positive score on the CAGE was 8.6 percent with males, smokers, and blue collar and unemployed persons being more likely to score positive. The positive predictive value was .68. Primarily, persons with moderate alcohol problems were identified. Results show that the CAGE instrument is a useful screening device for identifying those with mild to moderate substance abuse problems, increasing the opportunity for intervention prior to serious medical complications. The instrument is easily administered, and has demonstrated relatively high levels of sensitivity and specificity. When combined with assessment and motivational interviews, the CAGE shows promise in the secondary prevention of substance abuse and related health problems.  相似文献   
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