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191.
Lifetime cancer potency of alfatoxin was assessed based on the Yeh et al. study from China in which both aflatoxin exposure and hepatitis B prevalence were measured. This study provides the best available information for estimating the carcinogenic risk posed by aflatoxin to the U.S. population. Cancer potency of aflatoxin was estimated using a biologically motivated risk assessment model. The best estimate of aflatoxin potency was 9 (mg/kg/day)−1 for individuals negative for hepatitis B and 230 (mg/kg/day)−1 for individuals positive for hepatitis B.  相似文献   
192.
The focus of recent stratification research demonstrates increasing recognition of the structured nature of social inequality. Among the forms these efforts have taken has been the development of a number of models drawing attention to the importance of various labor market decisions or cleavages. The crucial role which restricted labor mobility must play in maintaining these cleavages, while largely untested, has long been recognized. We argue that analysis of the patterns of job sequencing can be used to draw important inferences regarding the existence and character of labor market structures. From this premise, we use job transition data to test a number of propositions derived from dual economy theory, relating to the extent of intersectoral moves and the patterns of intersectoral and intrasectoral moves. Using log-linear methods, we find the hypothesized restricted evidence of intersectoral job shifts and also find patterns of intrasectoral moves indicative of the pervasiveness of rigidly structured internal labor markets in the core. While these results are consistent with a dualistic interpretation, they are equally as consistent with any model emphasizing the existence of strong intrafirm and intraindustry job structures.  相似文献   
193.
凯瑞·布朗是享誉世界的中国问题研究专家。2019年1月,凯瑞·布朗在访谈中谈到了他对中国共产党的文化以及中国故事的理解。他主张以中国共产党的历史为基础,植根中国的传统文化来理解中国共产党的文化,理解中国故事,分析中国政治与全球秩序。中国共产党的力量植根于改革开放的伟大进程中;一部成功的中国故事,就是具有积极愿景的未来的故事,是一个信仰团体的故事,是道德正义的故事;只有植根中国历史与文化,才可以理解并解决中西方的“幻象冲突”问题。  相似文献   
194.
A two sample cest is proposea ior Liie hypuLiiefexo in.; LUSL observations from a second sample are equivalent, in distribution, to the smallest of r independent realisations of the first sample.

Assuming H to be true the efficiency of parameter estimation for the exponential and normal distributions is then considered  相似文献   
195.
For the portfolio problem with unknown parameter values, we compare the conventional certainty equivalence portfolio choice with the optimal Bayes portfolio. In the important single risky asset case a diffuse Bayes rule leads to portfolios that differ significantly from those suggested by a certainty equivalence rule which we show are inadmissible relative to a quadratic utility function for the range of parameters we consider. These results are invariant to arbitrary changes in the utility function parameters. We illustrate the results using a simple mutual fund example.  相似文献   
196.
Many methods are available for computing a confidence interval for the binomial parameter, and these methods differ in their operating characteristics. It has been suggested in the literature that the use of the exact likelihood ratio (LR) confidence interval for the binomial proportion should be considered. This paper provides an evaluation of the operating characteristics of the two‐sided exact LR and exact score confidence intervals for the binomial proportion and compares these results to those for three other methods that also strictly maintain nominal coverage: Clopper‐Pearson, Blaker, and Casella. In addition, the operating characteristics of the two‐sided exact LR method and exact score method are compared with those of the corresponding asymptotic methods to investigate the adequacy of the asymptotic approximation. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
197.
Although researchers have identified the more immediate mechanisms of change in family‐based treatments for juvenile justice‐involved youths, it is not known whether these same mechanisms continue to prevent criminal offending into adulthood. The present study evaluated whether caregiver‐directed improvements in family relations, youth prosocial peer relations, and youth academic performance during multisystemic therapy (MST) for serious and violent juvenile offenders had an impact on young adult involvement in criminal activity and sentencing 10.2 years following treatment. The results showed that improvements in family relations were associated with reduced odds of criminal outcomes a decade later for former MST participants. Furthermore, improvements in youth prosocial peer relations and academic performance were also related to lower odds of long‐term criminal activity. These results are consistent with the underlying theory of change in family‐based treatments and demonstrate that caregivers are critical to achieving and sustaining decreased antisocial behavior for youths with serious and violent criminal histories.  相似文献   
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