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891.
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
892.
Certain motor vehicle safety standards stipulate a collision test speed and a set of performance criteria that vehicles must satisfy during or after the collision test. For example, Federal Motor Vehicle Safety Standard 301 requires a 30 mile per hour (mph) barrier collision and specifies a certain maximum allowable limit on the total spillage of fuel. Vehicle designs are required to meet this standard; however, when collision tests are conducted at speeds higher than the standard, vehicles do not always satisfy the performance criteria. This paper develops a mathematical model for estimating the probability of meeting the standard by using a Bayesian framework to incorporate engineering judgment with collision test results. The model is based on the idea that there are random features to a vehicle's ability to meet performance standards in a collision, especially at such elevated speeds. Example calculations are included to illustrate the estimation of the probability of meeting the standard and to compare it with a maximum likelihood approach. 相似文献
893.
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
894.
895.
896.
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.
相似文献
Markus M. GrabkaEmail: |
897.
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
898.
899.
Wade M. Cole 《Sociological Forum》2009,24(3):563-588
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
900.
George P. Knight Delfino Vargas‐Chanes Sandra H. Losoya Sonia Cota‐Robles Laurie Chassin Joanna M. Lee 《Journal of research on adolescence》2009,19(4):625-653
This study examines changes over time in ethnic affirmation/belonging and ethnic identity achievement, Spanish language use, English language use, Mexican/Mexican‐American affiliation/identification and Anglo affiliation/identification in a sample of Mexican‐American adolescents participating in a longitudinal study of juvenile offenders. The Multigroup Ethnic Identity Measure and the Acculturation Rating Scale for Mexican Americans‐II were completed by the Mexican‐American adolescents 7 times over a 3‐year period. The findings from longitudinal growth modeling analyses and growth mixture modeling analyses indicate that there is heterogeneity in the initial scores and changes over time on these variables that are related to markers for the cultural qualities of the home environment (i.e., generational status and mother's most frequent language use). In contrast to expectations, marginalized or assimilated acculturation trajectories/types were not overrepresented in this sample of adolescent offenders. Implications for our understanding of the nature of acculturation and enculturation processes and the way these processes are studied are discussed. 相似文献