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791.
Drawing on Delgado and Yosso’s counterstory, Yosso’s community cultural wealth, and Alsup’s borderland discourses, the authors, who are women of color academics, use narratives from their lives to discuss the ways in which they draw on resources in managing and reconfiguring their multiple identities within the academy. These include identities of scholars, mentors, teachers, community members, mothers, and partners. They suggest that rather than merely being socialized into cultural reproduction, as much of the literature oriented toward women of color advises them to do in order to become successful, they seek to actually engage in transforming their roles and that of the academy by consciously and repeatedly making present and visible facets of identity that have previously been more-or-less absent in higher education. By presenting these counter-narratives the authors attempt to engage with ways of self-positioning that are, especially for women of color in academia, not frequently discussed or presented.  相似文献   
792.
Two heuristics based on branch and bound (B&B) are developed to solve closed-loop material requirements planning (MRP) lot-sizing problems that have general product structures and variable costs. A “look ahead method'’(LAM) heuristic allows for variable production/purchasing costs and uses a single-level B&B procedure to rapidly improve lower bound values; thus, LAM efficiently uses computer-storage capacity and allows solution of larger problems. The “total average modification'’(TAM) heuristic uses B&B, applied level by level, and modified setup and carrying costs to solve the variable production/purchasing costs MRP lot-sizing problem. LAM and TAM are tested on problems and compared to heuristics in the literature. TAM may be used to solve large MRP lot-sizing problems encountered in practice.  相似文献   
793.
Scientific techniques for inventory management typically are applied to systems containing many items. Such techniques require an estimation of the demand variance (and mean) of each item from historical data. This research demonstrates a significant potential for improvement in system cost performance from using least-squares regression fits of a variance-to-mean functional relation instead of the standard statistical variance estimate. Even when there is a moderate degree of heterogeneity among items and when the form of the variance-to-mean relation is misspecified, substantial cost savings may be realized. The cost of statistical uncertainty may be reduced by half. The research also provides evidence that system cost is fairly insensitive to the number of items used to fit the regression. This paper provides the underlying reason why a regression-derived variance estimator yields lower cost: it is less variable than the usual individual item variance estimator.  相似文献   
794.
This paper develops a warning zone approach to make variance investigation decisions for a multiperiod process. The assumed cost generation process varies between an in-control and out-of-control state. These states cannot be directly observed, but must be inferred from the reported cost variances. Using the warning zone method of inference, the manager investigates the process whenever an upper threshold is exceeded or a lower threshold is exceeded for two consecutive periods. A four-state Markov chain models the resulting decision process. Steady state probabilities are derived for this chain and are used to obtain explicit formulas for the effectiveness and efficiency of the decision process. These formulas permit computation of the cost savings attainable by the warning zone method. Compared to other decision rules, the warning zone method is much simpler than the theoretically optimal Bayesian revision method, but uses more information than the Markovian control limit method. Numerical comparison of results shows that the warning zone method usually captures most of the available cost savings, even in cases where the Markovian control limit method does not perform well.  相似文献   
795.
We explored the influences of women's social learning, marital resources and constraints, and exposure to norms about women's family roles on their views about wife hitting or beating among 5,450 participants in the 2005 Egypt Demographic and Health Survey. One half justified wife hitting or beating for some reason. Women from rural areas who were exposed to domestic violence more often justified such acts. Dependent wives whose husbands had more schooling, were blood relatives, and were coresident more often justified such acts. In settings where women tended to marry at older ages, women less often justified such acts. Women's resources and constraints in marriage accounted for the largest share of the variability in their attitudes about domestic violence against women.  相似文献   
796.
The positive association between moderate alcohol consumption and wages is well documented in the economic literature. Positive health effects as well as networking mechanisms serve as explanations for the “alcohol–income puzzle.” Using individual-based microdata from the SOEP for 2006, we confirm that this relationship exists for Germany as well. More importantly, we shed light on the alcohol–income puzzle by analyzing, for the first time, the association between beverage-specific drinking behavior and wages. In our analysis, we disentangle the general wage effect of drinking into diverse effects for different types of drinkers. Mincerian estimates reveal significant and positive relationships between wine drinkers and wages as well as between multiple beverage drinkers and wages. When splitting the sample into age groups, the “drinking gain” disappears for employees under the age of 35 and increases in size and significance for higher age groups. We also find a “beer gain” for the oldest age group and male residents of rural areas as well as a “cocktail gain” for residents of urban areas. Several explanations for our empirical results are discussed in view of the likelihood that the alcohol–income puzzle is a multicausal phenomenon.
Markus M. GrabkaEmail:
  相似文献   
797.
Our understanding of the underlying demographic components of population change in new Hispanic destinations is limited. In this paper, we (1) compare Hispanic migration patterns in traditional settlement areas with new growth in emerging Hispanic destinations; (2) examine the role of immigration vis‐à‐vis domestic migration in spurring Hispanic population redistribution; and (3) document patterns of migrant selectivity, distinguishing between in‐migrants and non‐migrant Hispanics at both the origin and destination. We use several recent datasets, including the 1990 and 2000 Public Use Microdata Samples (which include new regional geocodes), and the 2005 and 2006 files of the American Community Survey. Our results document the widespread dispersion of the Hispanic population over the 1990–2006 period from established Hispanic gateways into new Hispanic areas and other parts of the country. Nearly one‐half of Hispanic net migration in new destinations comes from domestic gains. In contrast, both established and other Hispanic areas depend entirely on immigration, with each losing domestic migrants to high growth areas. Migrant flows also are highly differentiated by education, citizenship, and nativity. To fully understand the spatial diffusion of Hispanics requires a new appreciation of the complex interplay among immigration, internal domestic migration, and fertility.  相似文献   
798.
799.
800.
What factors determine whether and how deeply countries will commit to the international human rights regime? Using data for up to 142 countries between 1966 and 2000, this article analyzes patterns of membership to the International Human Rights Covenants. The analysis produced two main conclusions. First, the potential costs associated with joining a treaty, rather than its substantive content, motivates the decision to join. Treaties that protect different rights but establish comparable implementation mechanisms exhibit similar patterns of membership, whereas treaties that protect identical rights but establish different implementation provisions exhibit dissimilar patterns of membership. Second, rates of treaty membership differ by level of commitment. Countries that sign human rights treaties differ from countries that ratify. Results are interpreted with respect to four theories of commitment and compliance: realism, liberalism, constructivism, and sociological institutionalism. Theories that emphasize the importance of a treaty’s costs (realism and institutionalism) fare better than theories that prioritize a treaty’s content (liberalism and constructivism).  相似文献   
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