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41.
We estimate a mixed logit model of the demand for local news service. Results provide evidence that suggest the representative consumer values more diverse news, more coverage of multicultural issues, and more information on community news, and has a distaste for advertising. Demand estimates are used to calculate the impact on consumer welfare from a marginal decrease in the number of independent television stations that lowers the amount of diversity, multiculturalism, community news, and advertising. Consumer welfare decreases, but the losses are smaller in large markets. For example, small‐market consumers lose $45 million annually while large‐market consumers lose $13 million. (JEL C9, C25, L13, L82, L96)  相似文献   
42.
Several researchers have proposed solutions to control type I error rate in sequential designs. The use of Bayesian sequential design becomes more common; however, these designs are subject to inflation of the type I error rate. We propose a Bayesian sequential design for binary outcome using an alpha‐spending function to control the overall type I error rate. Algorithms are presented for calculating critical values and power for the proposed designs. We also propose a new stopping rule for futility. Sensitivity analysis is implemented for assessing the effects of varying the parameters of the prior distribution and maximum total sample size on critical values. Alpha‐spending functions are compared using power and actual sample size through simulations. Further simulations show that, when total sample size is fixed, the proposed design has greater power than the traditional Bayesian sequential design, which sets equal stopping bounds at all interim analyses. We also find that the proposed design with the new stopping for futility rule results in greater power and can stop earlier with a smaller actual sample size, compared with the traditional stopping rule for futility when all other conditions are held constant. Finally, we apply the proposed method to a real data set and compare the results with traditional designs.  相似文献   
43.
Objective. Although research suggests that national forces can play a role in local and state elections, most of this work has only recently begun to examine the potential role of national forces in state or local ballot initiative or referenda elections. Methods. Our research addresses this gap in the literature by exploring the influence of national forces, such as the timing of elections, Supreme Court rulings, the activities of interest groups, and public opinion, on state direct legislation elections. We incorporate national forces into the morality politics framework and derive specific hypotheses. We then test these hypotheses by conducting a multivariate analysis of county–level voting patterns across 16 abortion–related direct legislation elections. Results. Our results confirm most of the hypotheses derived from the morality politics framework, including those concerning the role of national forces. Conclusions. Voting patterns on abortion tend to be influenced by the presence of presidential elections, Supreme Court rulings, interest–group activity, public opinion, partisanship, college education, and conservative religious forces. We discuss the implications of our findings for research on elections, abortion policy, and morality politics.  相似文献   
44.
This study was conducted in the southwest area of Brisbane, Australia, and is designed to explore and assess the health needs of Vietnamese migrant women. The needs of this group are becoming increasingly urgent due to ageing of the original immigrant refugee community and decreased capacity for support from their children and families. The study used a qualitative research strategy involving focus groups and in‐depth interviews with Vietnamese women between 18–65 years and interviews with Vietnamese health care providers. It shows that the women have had to deal with culture shock, low self‐esteem, lack of friends and relatives, unrecognized professional skills and most importantly in health terms, low socioeconomic status. Significant barriers to access health services and to improved health and well‐being were also identified, such as language difficulties, transportation, time, and knowledge about health education. Recognition of specific requirements of sub‐populations as well as broader socio‐economic and cultural determinants of health should be a guide to more effective planning and implementation of health promotion strategies. The changing needs, over time, of these sub‐populations should also be recognized.  相似文献   
45.
Objective. An individual's personal experiences and perception of the collective experience are often linked to political attitudes, especially those concerning the national economy. In this article, we examine whether personal concern about terrorism and perceptions of public concern about terrorism affect attitudes about counterterrorism policies. In addition, we evaluate which factor is the strongest predictor across several counterterrorism policies. Method. We analyze individual‐level survey data collected during the fall of 2001. Results. Our results indicate that perceptions of public concerns are the strongest and most consistent predictor of policy attitudes about terrorism. Conclusion. The implications for theory about perceptions of public opinion and the competing role of personal interest and sociotropic concern are discussed.  相似文献   
46.
Alexander Wendt raises many interesting questions in this book, but to get to the answers he wants, he relies on a misunderstanding of the nature of the quantum states of macroscopic objects.  相似文献   
47.
Lester D  Templer DI  Abdel-Khalek A 《Omega》2006,54(3):255-260
Data are reported from samples of undergraduates around the world who have been administered Templer's Death Anxiety Scale. Data from 24 American samples and from 16 nations were identified. Strong sex differences were found and an association between the scores of men and women.  相似文献   
48.
Root cause analysis can be used in foodborne illness outbreak investigations to determine the underlying causes of an outbreak and to help identify actions that could be taken to prevent future outbreaks. We developed a new tool, the Quantitative Risk Assessment-Epidemic Curve Prediction Model (QRA-EC), to assist with these goals and applied it to a case study to investigate and illustrate the utility of leveraging quantitative risk assessment to provide unique insights for foodborne illness outbreak root cause analysis. We used a 2019 Salmonella outbreak linked to melons as a case study to demonstrate the utility of this model (Centers for Disease Control and Prevention [CDC], 2019). The model was used to evaluate the impact of various root cause hypotheses (representing different contamination sources and food safety system failures in the melon supply chain) on the predicted number and timeline of illnesses. The predicted number of illnesses varied by contamination source and was strongly impacted by the prevalence and level of Salmonella contamination on the surface/inside of whole melons and inside contamination niches on equipment surfaces. The timeline of illnesses was most strongly impacted by equipment sanitation efficacy for contamination niches. Evaluations of a wide range of scenarios representing various potential root causes enabled us to identify which hypotheses, were likely to result in an outbreak of similar size and illness timeline to the 2019 Salmonella melon outbreak. The QRA-EC framework can be adapted to accommodate any food–pathogen pairs to provide insights for foodborne outbreak investigations.  相似文献   
49.
This paper considers regression models for cross‐section data that exhibit cross‐section dependence due to common shocks, such as macroeconomic shocks. The paper analyzes the properties of least squares (LS) estimators in this context. The results of the paper allow for any form of cross‐section dependence and heterogeneity across population units. The probability limits of the LS estimators are determined, and necessary and sufficient conditions are given for consistency. The asymptotic distributions of the estimators are found to be mixed normal after recentering and scaling. The t, Wald, and F statistics are found to have asymptotic standard normal, χ2, and scaled χ2 distributions, respectively, under the null hypothesis when the conditions required for consistency of the parameter under test hold. However, the absolute values of t, Wald, and F statistics are found to diverge to infinity under the null hypothesis when these conditions fail. Confidence intervals exhibit similarly dichotomous behavior. Hence, common shocks are found to be innocuous in some circumstances, but quite problematic in others. Models with factor structures for errors and regressors are considered. Using the general results, conditions are determined under which consistency of the LS estimators holds and fails in models with factor structures. The results are extended to cover heterogeneous and functional factor structures in which common factors have different impacts on different population units.  相似文献   
50.
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