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451.
Goodness-of-fit tests for the family of symmetric normal inverse Gaussian distributions are constructed. The tests are based on a weighted integral incorporating the empirical characteristic function of suitably standardized data. An EM-type algorithm is employed for the estimation of the parameters involved in the test statistic. Monte Carlo results show that the new procedure is competitive with classical goodness-of-fit methods. An application with financial data is also included.  相似文献   
452.
Creating value through outsourcing has emerged as a popular competitive strategy for firms in various industries. In order to survive in the domestic and international marketplaces, firms, especially in developed countries, are seeking opportunities offshore, which is one focus of globalization. Offshore outsourcing has emerged as a popular competitive strategy and emerging markets have become increasingly attractive locations. As firms in developed countries (e.g., the US) continue to face enormous challenges to sustain competitive advantage, outsourcing to emerging markets is becoming an increasingly important source of business renewal and corporate transformation.In spite of the growing strategic significance of sourcing, we have limited knowledge of offshoring and outsourcing to emerging markets. The objectives of this review are fourfold: (1) to provide a better understanding of the concepts of offshoring and outsourcing business models, (2) to discuss relevant theoretical perspectives related to outsourcing, (3) to present a taxonomy of outsourcing strategies drawing on the extant literature, and (4) to discuss public policy implications. Conclusions and direction for future research are provided.  相似文献   
453.
Despite the substantial amount of literature focusing on social support for pregnant and parenting adolescents, few studies have directly examined the relationships among stress and social support across their transition to parenting. The present study investigates the nature of the relationship between stress and support both before and after the birth of the baby. Two groups of adolescent females (one group facing parenthood and one not) completed measures of support and stress across a 7-month period (N = 231) to coincide with the transition to parenthood. In general, support and stress were negatively related when measured concurrently and positively related over time for parenting adolescents but not the non-parenting group. Understanding how long social support impacts stress will enable practitioners to identify when best to provide interventions for pregnant and parenting adolescents.  相似文献   
454.
A characterization of the uniform distribution based on distributions of spacings is presented which extends the existing result in this direction. Also, a result on the distribution of spacings for distributions close to the uniform one is discussed.  相似文献   
455.
Previous research suggests that when there is a high level of inequality, there is a low rate of participation. Two arguments are generally offered: First, inequality depresses participation because people from different status groups have fewer opportunities to share common goals. Second, people may participate more in civic and social life when they have more resources. However, until now, these explanations have not been separated empirically. Using EU-SILC data for 24 European countries, we analyze how income inequality is related to civic and social participation. Our results indicate that the main effects of inequality manifest via resources at the individual and societal level. However, independent of these resources, higher inequality is associated with lower civic participation. Furthermore, inequality magnifies the relationship between income and participation. This finding is in line with the view that inter-individual processes explain why inequality diminishes participation.  相似文献   
456.
When assessing risks posed by environmental chemical mixtures, whole mixture approaches are preferred to component approaches. When toxicological data on whole mixtures as they occur in the environment are not available, Environmental Protection Agency guidance states that toxicity data from a mixture considered “sufficiently similar” to the environmental mixture can serve as a surrogate. We propose a novel method to examine whether mixtures are sufficiently similar, when exposure data and mixture toxicity study data from at least one representative mixture are available. We define sufficient similarity using equivalence testing methodology comparing the distance between benchmark dose estimates for mixtures in both data‐rich and data‐poor cases. We construct a “similar mixtures risk indicator”(SMRI) (analogous to the hazard index) on sufficiently similar mixtures linking exposure data with mixtures toxicology data. The methods are illustrated using pyrethroid mixtures occurrence data collected in child care centers (CCC) and dose‐response data examining acute neurobehavioral effects of pyrethroid mixtures in rats. Our method shows that the mixtures from 90% of the CCCs were sufficiently similar to the dose‐response study mixture. Using exposure estimates for a hypothetical child, the 95th percentile of the (weighted) SMRI for these sufficiently similar mixtures was 0.20 (i.e., where SMRI <1, less concern; >1, more concern).  相似文献   
457.
The radical changes that are taking place in the country, and which have led to a total crisis both in the political and the economic and social spheres, have affected all segments and groups of the population—men and women, rich and poor, old people and children, and those engaged in physical and mental work.  相似文献   
458.
459.
For a class of voting rules, which includes Approval and Cumulative Voting, it is shown how to find and analyze all possible outcomes that arise with a specified profile, and, conversely, how to start with a potential region and determine whether there exist supporting profiles. The geometry of these regions is determined by the “Reversal symmetry” portion of a profile; i.e., components of the A\succ B\succ C, C\succ B\succ A{A\succ B\succ C, C\succ B\succ A} type.  相似文献   
460.
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