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921.
The Relative Weights of Direct and Indirect Experiences in the Formation of Environmental Risk Beliefs
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Direct experiences, we find, influence environmental risk beliefs more than the indirect experiences derived from outcomes to others. This disparity could have a rational basis. Or it could be based on behavioral proclivities in accord with the well‐established availability heuristic or the vested‐interest heuristic, which we introduce in this article. Using original data from a large, nationally representative sample, this article examines the perception of, and responses to, morbidity risks from tap water. Direct experiences have a stronger and more consistent effect on different measures of risk belief. Direct experiences also boost the precautionary response of drinking bottled water and drinking filtered water, while indirect experiences do not. These results are consistent with the hypothesized neglect of indirect experiences in other risk contexts, such as climate change. 相似文献
922.
Dejian Lai Qiang Zhang Jose-Miguel Yamal Paula T. Einhorn Barry R. Davis 《统计学通讯:理论与方法》2017,46(18):8943-8951
Effective recruitment is a prerequisite for successful execution of a clinical trial. ALLHAT, a large hypertension treatment trial (N = 42,418), provided an opportunity to evaluate adaptive modeling of recruitment processes using conditional moving linear regression. Our statistical modeling of recruitment, comparing Brownian and fractional Brownian motion, indicates that fractional Brownian motion combined with moving linear regression is better than classic Brownian motion in terms of higher conditional probability of achieving a global recruitment goal in 4-week ahead projections. Further research is needed to evaluate how recruitment modeling can assist clinical trialists in planning and executing clinical trials. 相似文献
923.
The purpose of this study was to provide an initial investigation into the work–family conflict (WFC) experiences of individuals who hold a second job. Specifically, we proposed two opposing theoretical arguments regarding the relationship between WFC and four measures of well-being: life satisfaction, physical health, emotional exhaustion, and exercise for individuals who hold two jobs. In a sample of individuals working two jobs, we tested whether the effects of WFC arising from the first job and from the second job exerted an additive or interactive effect on employee well-being. Our results indicated that for emotional exhaustion, physical symptoms, and life satisfaction, the effects of WFC from two jobs are interactive; but that for exercise, the effects of WFC from two jobs are additive. In both cases, the additional WFC experienced as a result of working a second job contributed to the prediction of employee well-being over and above WFC from the first job. Results are discussed within the context of relevant theory, and suggestions are made for future research. 相似文献
924.
胡星铭 《浙江大学学报(人文社会科学版)》2018,48(3):173
当代知识论越来越重视认知价值的研究,但从认知价值角度去重新思考传统怀疑主义问题的研究却很少。历史上的怀疑主义者既认为我们无法拥有任何知识,又主张我们应该悬置判断。因此,他们不仅预设了一个高的知识标准,而且预设了一个价值标准:任何达不到知识标准的认知状态都是没有认知价值的。但这个价值标准是错误的,所以我们即使无法达到怀疑主义者所设定的知识标准,也不必悬置判断。假设怀疑主义者认为我们无法拥有任何知识,同时认可“有些达不到知识标准的认知状态也有认知价值”,那么怀疑主义就没有很大的威胁性,因为即使我们无法获取知识,也可以获得具有认知价值的东西,取得认知进步。此外,摩尔主义、语境主义、溯因主义这几种对怀疑主义的主要回应是否成功,最终都依赖于对认知价值的讨论。 相似文献
925.
Nguyen T. P. Thao 《Asian Social Work and Policy Review》2016,10(2):225-236
Married Vietnamese immigrant women often face multiple stressors related to sociocultural adaptation and new family lives in South Korea. The purpose of this paper is to identify the different influences of acculturative and family life stress on depressive symptoms among Vietnamese immigrant wives. Data were collected through a questionnaire survey of 301 married Vietnamese immigrant women residing in South Korea. The study utilized linear regression analysis to test the relationships between the variables. The findings show that both acculturative and family life stress are positively related to depressive symptoms. Family life stress influences depressive symptoms to a greater extent than acculturative stress. The study emphasizes the significance of family‐related stress on mental health among married Vietnamese immigrant women in Korea and provides some implications for research, clinical practice, and policy. 相似文献
926.
This article proposes an approach to flood risk communication that gives particular emphasis to the distinction between prevention and promotion motivation. According to E. Tory Higgins, the promotion system and the prevention system are assumed to coexist in every person, but one or the other may be temporarily or chronically more accessible. These insights have far‐reaching implications for our understanding of people's reasoning about risks. Flood risk communication framed in terms of prevention involves the notions of chance and harm, woven into a story about particular events that necessitate decisions to be more careful about safety issues and protect one's family and oneself from danger. The article describes how the insights worked out in practice, using a flood risk communication experiment among a sample from the general population in a highly populated river delta of the Netherlands. It had a posttest‐only control group design (n = 2,302). The results showed that risk communication had a large effect on the participants’ responses and that this effect was higher among chronic prevention‐focused people than among others. Any information that increased the fit between a prevention‐framed message and a person's chronic prevention motivation produced stronger situationally induced, prevention‐focused responses. This may significantly improve communication about risks. In contrast, the notion of water city projects, featuring waterside living, had more appeal to promotion‐focused people. 相似文献
927.
Estimation of benchmark doses (BMDs) in quantitative risk assessment traditionally is based upon parametric dose‐response modeling. It is a well‐known concern, however, that if the chosen parametric model is uncertain and/or misspecified, inaccurate and possibly unsafe low‐dose inferences can result. We describe a nonparametric approach for estimating BMDs with quantal‐response data based on an isotonic regression method, and also study use of corresponding, nonparametric, bootstrap‐based confidence limits for the BMD. We explore the confidence limits’ small‐sample properties via a simulation study, and illustrate the calculations with an example from cancer risk assessment. It is seen that this nonparametric approach can provide a useful alternative for BMD estimation when faced with the problem of parametric model uncertainty. 相似文献
928.
Urban and agricultural soils: conflicts and trade-offs in the optimization of ecosystem services 总被引:2,自引:0,他引:2
H. Setälä R. D. Bardgett K. Birkhofer M. Brady L. Byrne P. C. de Ruiter F. T. de Vries C. Gardi K. Hedlund L. Hemerik S. Hotes M. Liiri S. R. Mortimer M. Pavao-Zuckerman R. Pouyat M. Tsiafouli W. H. van der Putten 《Urban Ecosystems》2014,17(1):239-253
On-going human population growth and changing patterns of resource consumption are increasing global demand for ecosystem services, many of which are provided by soils. Some of these ecosystem services are linearly related to the surface area of pervious soil, whereas others show non-linear relationships, making ecosystem service optimization a complex task. As limited land availability creates conflicting demands among various types of land use, a central challenge is how to weigh these conflicting interests and how to achieve the best solutions possible from a perspective of sustainable societal development. These conflicting interests become most apparent in soils that are the most heavily used by humans for specific purposes: urban soils used for green spaces, housing, and other infrastructure and agricultural soils for producing food, fibres and biofuels. We argue that, despite their seemingly divergent uses of land, agricultural and urban soils share common features with regards to interactions between ecosystem services, and that the trade-offs associated with decision-making, while scale- and context-dependent, can be surprisingly similar between the two systems. We propose that the trade-offs within land use types and their soil-related ecosystems services are often disproportional, and quantifying these will enable ecologists and soil scientists to help policy makers optimizing management decisions when confronted with demands for multiple services under limited land availability. 相似文献
929.
Thomas S. Shively Thomas W. Sager Stephen G. Walker 《Journal of the Royal Statistical Society. Series B, Statistical methodology》2009,71(1):159-175
Summary. The paper proposes two Bayesian approaches to non-parametric monotone function estimation. The first approach uses a hierarchical Bayes framework and a characterization of smooth monotone functions given by Ramsay that allows unconstrained estimation. The second approach uses a Bayesian regression spline model of Smith and Kohn with a mixture distribution of constrained normal distributions as the prior for the regression coefficients to ensure the monotonicity of the resulting function estimate. The small sample properties of the two function estimators across a range of functions are provided via simulation and compared with existing methods. Asymptotic results are also given that show that Bayesian methods provide consistent function estimators for a large class of smooth functions. An example is provided involving economic demand functions that illustrates the application of the constrained regression spline estimator in the context of a multiple-regression model where two functions are constrained to be monotone. 相似文献
930.
Nicholas W. Gillham 《Significance》2009,6(3):132-135
Sir Francis Galton, scientist, African Explorer and statistician, was a key figure in statistical history. He was the man who devised the statistical concepts of regression and correlation. He was also Charles Darwin's cousin. And, inspired by his reading of Darwin, he was the founder of eugenics: the "science" of improving the human race through selective breeding. Nicholas Gillham tells of a darker side to statistics and heredity. 相似文献