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51.
This article compares the performance of the expected utility (EU) and lottery-dependent expected utility (LDEU) models in predicting the actual choices of experimental subjects among risky options. In the process, we present two approaches for calibrating the LDEU model for an individual decision maker. The results indicate that while LDEU exhibits a higher potential for correctly predicting choice, the version of the model calibrated by indifference judgments does not outperform EU. We suggest a functional form for the parametric functions that defines the LDEU model, and discuss ways in which this function can be incorporated into choice-based assessment approaches to improve predictions.This research was supported in part by the Business Associates Fund at the Fuqua School of Business, Duke University.  相似文献   
52.
ABSTRACT

Objectives: To examine how tobacco use and depression/anxiety disorders are related to disturbed sleep in college students. Participants: 85,138 undergraduate respondents (66.3% female, 74.5% white, non-Hispanic, ages 18–25) from the Spring 2011 American College Health Association–National College Health Assessment II database. Methods: Multivariate analyses of tobacco use (none, intermediate, daily) and mental health (diagnosed and/or symptomatic depression or anxiety) were used to predict sleep disturbance. Results: Daily tobacco use was associated with more sleep problems than binge drinking, illegal drug use, obesity, gender, and working >20 hours/week. Students with depression or anxiety reported more sleep disturbances than individuals without either disorder, and tobacco use in this population was associated with the most sleep problems. Conclusions: Tobacco use and depression/anxiety disorders are both independently associated with more sleep problems in college students. Students with depression and/or anxiety are more likely to be daily tobacco users, which likely exacerbates their sleep problems.  相似文献   
53.
Estimation of long-run inefficiency levels: a dynamic frontier approach   总被引:2,自引:0,他引:2  
Cornwell, Schmidt, and Sickles (1990) and Kumbhakar (1990), among others, developed stochasticfrontier production models which allow firm specific inefficiency levels to change over time. These studies assumed arbitrary restrictions on the short-run dynamics of efficiency levels which have little theoretical justification. Further, the models are inappropriate for estimation of long-run efficiencies. We consider estimation of an alternative frontier model in which firmspecific technical inefficiency levels are autoregressive. This model is particularly useful to examine a potential dynamic link between technical innovations and production inefficiency levels. We apply our methodology to a panel of US airlines.  相似文献   
54.
Abstract

Objective: The aim of this Canadian study was to assess student behavioral response to disease transmission risk, while identifying high microbial deposition/transmission sites. Participants: A student survey was conducted during October 2009. Methods: The methods included a survey of students to assess use of health services, vaccination compliance, and hygiene along with a microbial analysis of potential transmission sites targeting specific residence buildings on campus. Results: Results indicated that most students maintained that they were worried about H1N1 and reported making changes in hygienic behavior, with the majority not planning to be vaccinated. The microbial analysis indicated contamination of fomites in co-ed residences to be higher than either male or female student residences. Conclusions: A consideration of physical space along with behavioral factors is required in order to properly assess risk pathways in the establishment of an evidence-based infection control plan for universities and their contiguous communities.  相似文献   
55.
The New Zealand health system was substantially reformed in 1993 with the introduction of a purchaser–provider split, competitive contracting and managerialism. The new system failed to deliver the desired gains and, in 1996, the reforms were "reformed". While there has been widespread study of the 1993 reforms, there has been little discussion to date of the 1996 changes and the emerging directions for New Zealand health policy and service delivery, which remain unclear. This paper discusses the New Zealand health reforms of the 1990s. It briefly outlines the 1993 reforms and their results. Next, it details the 1996 "reforms". Third, it discusses developments since 1996, some of which have emerged out of the 1993 reforms, but which have gathered momentum only since the 1996 changes were announced. In the conclusion, the paper lists some of the directions in which the New Zealand health sector appears to be heading, noting that there is a need for coordination of the sector, and for permanence.  相似文献   
56.
The present study replicated Jastrow's 1891 experiment concerning differences between male and female vocabulary. Participants were 20 male and 20 female Caucasian middle‐class college students. They recorded up to 100 nouns in a 15‐minute period. Results indicate that women have increased their use of unusual words compared to women in 1891. Males used more scientific words and more body part words than females. In contrast to the previous study, there are no significant differences between the sexes in use of animal, nature, and food words. Females used more clothing words than males in this study, as in the previous study, and produced more different words than males. Vocabulary changes appear to reflect changes in the social structure of the society.  相似文献   
57.
A hazard model of the probability of medical school drop-out in the UK   总被引:2,自引:0,他引:2  
Summary.  From individual level longitudinal data for two entire cohorts of medical students in UK universities, we use multilevel models to analyse the probability that an individual student will drop out of medical school. We find that academic preparedness—both in terms of previous subjects studied and levels of attainment therein—is the major influence on withdrawal by medical students. Additionally, males and more mature students are more likely to withdraw than females or younger students respectively. We find evidence that the factors influencing the decision to transfer course differ from those affecting the decision to drop out for other reasons.  相似文献   
58.
This paper looks at various issues that are of interest to the sports gambler. First, an expression is obtained for the distribution of the final bankroll using fixed wagers with a specified initial bankroll. Second, fixed percentage wagers are considered where the Kelly method is extended to the case of simultaneous bets placed at various odds; a computational algorithm is presented to obtain the Kelly fractions. Finally, the paper considers the problem of determining whether a gambling system is profitable based on the historical results of bets placed at various odds.  相似文献   
59.
Recent years have witnessed an increasing recognition of the role of grandparents in contemporary families. However, there has been little if any research which emphasises the roles and relationships of grandfathers. And while the more limited contribution of grandfathers compared to grandmothers remains a widespread perception, recent studies suggest that the importance of grandfatherhood for men has been considerably underestimated. Through reviewing the place of grandfathers within grandparenthood research, the article argues that understandings of grandfathers in terms of gender difference can be seen to reflect a feminised conception of grandparenting derived from the experience of grandmothers. The article then builds on this review by exploring how intersections of age identity and masculinity may influence the different ways in which grandfatherhood is understood and enacted.  相似文献   
60.
Risk-perception research plays an active role in discussions of risk-management alternatives. However, little guidance is provided regarding how public concerns should be weighed against other sources of cost and benefits. This paper reports the results of two experiments that measure tradeoffs among cost (in dollars), a quantitative risk measure (number of deaths or injuries), and several qualitative characteristics associated with perceived risk. Most subjects were willing to make the requested trade. However, the perceived risk information led others to reject the proposed technology.  相似文献   
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