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211.
South SJ  Crowder K  Pais J 《Demography》2011,48(4):1263-1292
Using data from the 1981, 1991, and 2001 waves of the Panel Study of Income Dynamics and several decennial censuses, we examine how characteristics of metropolitan areas are associated with black and white households’ neighborhood racial composition. Results from hierarchical linear models show that about 20% to 40% of the variation in the percentage of households’ tract population that is non-Hispanic white or non-Hispanic black exists across metropolitan areas. Over time, white households’ exposure to non-Hispanic white neighbors has declined, and their exposure to non-Hispanic black neighbors has increased; the reverse trends are observed for blacks. These trends cannot be attributed to changes in the ecological structure of metropolitan areas. Blacks have fewer white neighbors in large metropolitan areas containing sizable minority populations, and blacks have more white neighbors in metropolitan areas with high government employment. Whites have more black neighbors in metropolitan areas with high levels of government employment and ample new housing; whites have fewer black neighbors in metropolitan areas with a high level of municipal fragmentation. The association between metropolitan-area percentage black and tract percentage black is weaker among whites than among blacks, suggesting that whites are especially motivated to self-segregate in metropolitan areas with large black populations.  相似文献   
212.
Using a sample of 3,977 youths from the National Longitudinal Survey of Youth (NLSY97), this study examines the unique characteristics of single‐custodial‐father families with adolescents and the effects of single fathers' involvement and parenting on outcomes in emerging adulthood. Findings suggest that single‐custodial‐father families are distinct from single‐mother and 2‐biological‐parent families in terms of sociodemographic characteristics, parenting styles, and involvement. Parenting styles and involvement mediate the differences between single‐father families and 2‐parent families in terms of high school completion and disconnectedness and partially mediate differences for single‐custodial‐father families with a partner. Family and sociodemographic characteristics are also associated with being disconnected for adolescents residing with a cohabiting custodial father.  相似文献   
213.
China has been experiencing pronounced changes in its sex ratio, but little research has explored the consequences of these changes for sexual behavior and health. We merge data from the 1999-2000 Chinese Health and Family Life Survey with community-level data from the 1982, 1990, and 2000 Chinese censuses to examine the relationship between the local sex ratio and several dimensions of men's sexual behavior and sexual health. Multilevel logistic regression models show that, when faced with a relative abundance of age-matched women in their community, Chinese men are slightly less likely to have intercourse with commercial sex workers, but are more likely to engage in premarital noncommercial intercourse and to test positive for a sexually transmitted infection. These findings are consistent with hypotheses derived from demographic-opportunity theory, which suggests that an abundance of opposite-sex partners will increase the risk of early, frequent, and multi-partner sex and, through this, sexually transmitted infection risk.  相似文献   
214.
In this paper, we consider methods of inference for vector measures of inequality and poverty. These vector measures may consist of several different scalar measures of inequality or poverty in a single dimension, several scalar measures of poverty which use different poverty lines, or several scalar measures of inequality or poverty in different dimensions. Our proposed methods are illustrated with a Monte Carlo simulation and two empirical examples utilizing Canadian household data.  相似文献   
215.
Pricing below cost is often classified as “dumping” in international trade and as “predatory pricing” in local markets. It is legally prohibited from practice because of earlier findings that it leads to predatory behavior by either eliminating competition or stealing market share. This study shows that a stochastic exchange rate can create incentives for a profit‐minded monopoly firm to set price below marginal cost. Our result departs from earlier findings because the optimal pricing decision is based on a rational behavior that does not exhibit any malicious intent against the competition to be considered as violating anti‐trust laws. The finding is a robust result, because our analysis demonstrates that this behavior occurs under various settings such as when the firm (i) is risk‐averse, (ii) can postpone prices until after exchange rates are realized, (iii) is capable of manufacturing in multiple countries, and (iv) operates under demand uncertainty in addition to the random exchange rate.  相似文献   
216.
In emergent photovoltaics, nanoscale materials hold promise for optimizing device characteristics; however, the related impacts remain uncertain, resulting in challenges to decisions on strategic investment in technology innovation. We integrate multi‐criteria decision analysis (MCDA) and life‐cycle assessment (LCA) results (LCA‐MCDA) as a method of incorporating values of a hypothetical federal acquisition manager into the assessment of risks and benefits of emerging photovoltaic materials. Specifically, we compare adoption of copper zinc tin sulfide (CZTS) devices with molybdenum back contacts to alternative devices employing graphite or graphene instead of molybdenum. LCA impact results are interpreted alongside benefits of substitution including cost reductions and performance improvements through application of multi‐attribute utility theory. To assess the role of uncertainty we apply Monte Carlo simulation and sensitivity analysis. We find that graphene or graphite back contacts outperform molybdenum under most scenarios and assumptions. The use of decision analysis clarifies potential advantages of adopting graphite as a back contact while emphasizing the importance of mitigating conventional impacts of graphene production processes if graphene is used in emerging CZTS devices. Our research further demonstrates that a combination of LCA and MCDA increases the usability of LCA in assessing product sustainability. In particular, this approach identifies the most influential assumptions and data gaps in the analysis and the areas in which either engineering controls or further data collection may be necessary.  相似文献   
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Research shows that individuals living in the southern part of the United States express more negative racial attitudes than those living outside the South. Using data from The American National Election Study (NES), the purpose of this paper is to assess whether key factors often associated with the Southern attitude distinction are indeed more potent in the South than elsewhere. Drawing data from the 1980s, 1990s, and 2000s, we further assess whether the impact of the South has increased or decreased over time. Results indicate that the impact of the South is negligible at best. Findings do show that place does matter for conservatives. However, in this case, non-South location matters more than the South. Relative to their liberal counterparts, conservatives in the non-South espouse more individualistic beliefs than do their Southern counterparts. These findings are discussed within the dominant theoretical framework in this area.  相似文献   
220.
Uniformly most powerful Bayesian tests (UMPBTs) are a new class of Bayesian tests in which null hypotheses are rejected if their Bayes factor exceeds a specified threshold. The alternative hypotheses in UMPBTs are defined to maximize the probability that the null hypothesis is rejected. Here, we generalize the notion of UMPBTs by restricting the class of alternative hypotheses over which this maximization is performed, resulting in restricted most powerful Bayesian tests (RMPBTs). We then derive RMPBTs for linear models by restricting alternative hypotheses to g priors. For linear models, the rejection regions of RMPBTs coincide with those of usual frequentist F‐tests, provided that the evidence thresholds for the RMPBTs are appropriately matched to the size of the classical tests. This correspondence supplies default Bayes factors for many common tests of linear hypotheses. We illustrate the use of RMPBTs for ANOVA tests and t‐tests and compare their performance in numerical studies.  相似文献   
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