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51.
Whether on grounds of perceived safety, aesthetics, or overall quality of life, residents may wish to be aware of nearby energy sites such as nuclear reactors, refineries, and fracking wells. Yet people are not always accurate in their impressions of proximity. Indeed, our data show that only 54% of Americans living within 25 miles of a nuclear site say they do, and even fewer fracking-proximal (30%) and refinery-proximal (24%) residents respond accurately. In this article, we analyze factors that could either help people form more accurate perceptions or distort their impressions of proximity. We evaluate these hypotheses using a large national survey sample and corresponding geographic information system (GIS) data. Results show that among those living in close proximity to energy sites, those who perceive greater risk are less likely to report living nearby. Conversely, social contact with employees of these industries increases perceived proximity regardless of actual distance. These relationships are consistent across each site type we examine. Other potential factors—such as local news use—may play a role in proximity perception on a case-by-case basis. Our findings are an important step toward a more generalizable understanding of how the public forms perceptions of proximity to risk sites, showing multiple potential mechanisms of bias.  相似文献   
52.
Abstract

The problem of testing Rayleigh distribution against exponentiality, based on a random sample of observations is considered. This problem arises in survival analysis, when testing a linearly increasing hazard function against a constant hazard function. It is shown that for this problem the most powerful invariant test is equivalent to the “ratio of maximized likelihoods” (RML) test. However, since the two families are separate, the RML test statistic does not have the usual asymptotic chi-square distribution. Normal and saddlepoint approximations to the distribution of the RML test statistic are derived. Simulations show that saddlepoint approximation is more accurate than the normal approximation, especially for tail probabilities that are the main values of interest in hypothesis testing.  相似文献   
53.
A study was undertaken to test for anchoring effects when numerical probabilities were elicited for carcinogen hazard designations. Subjects were asked to assign probabilities to both probable and possible. The sequence was randomly varied so that half of the subjects evaluated probable first and half evaluated possible first. While there was no consensus on the numerical probabilistic meanings assigned to these verbal expressions, in general, probable was assigned a higher probability than possible and there were specific values that were assigned frequently, indicating some consistency in interpretation. There appeared to be a fairly constant scaling factor between the probabilities assigned to the designations. Anchoring was manifested in two ways: a smaller difference between the designations when they were evaluated in sequence than when they were evaluated in isolation, and assignment of readily accessible "benchmark" values such as 50% and 75%.  相似文献   
54.
基于CGSS 2015中的全国农户生活能源使用状况数据,本文运用Tobit回归模型分析了农户家庭的人力资本、社会资本、经济资本以及清洁能源的可获得对农户清洁能源消费的影响。研究发现:高人力资本与经济资本的农户使用“高品位”的清洁能源,但其实际的能源支出却低于使用传统能源的其他农户,出现品位与成本倒挂的现象;人力资本与经济资本对农户使用的清洁能源耗能和占比均有显著正向影响,相对于务农而言,外出务工对农户清洁能源的耗能量和占比的提升有着积极作用;农户与清洁能源供应点的距离与清洁能源耗能和占比均正相关;人力资本要素中家庭最高文化程度越高,清洁能源消费成本占总能源消费成本的比率越低,经济资本对农户清洁能源消费有正向影响,农户在清洁能源的获得较容易时则会增加对清洁能源的消费额度,并提升其消费比例。  相似文献   
55.
In this study we investigated the effects of seeking versus avoiding proximity to mother on children’s emotional recovery from a stressor. Sixty children 9–12 years underwent a moodinduction procedure and were randomly assigned to seek proximity from or avoid an image of their mothers. The effect of this manipulation on children’s self‐reported negative emotions, skin conductance and heart rate variability (respiratory sinus arhythmia) was assessed. Higher levels of attachment anxiety were linked to more self‐reported sadness when children had to avoid mother, but no evidence for such an effect was found on a physiological level. For avoidant attachment, a similar pattern of results emerged, but both for self‐reported sadness and skin conductance.  相似文献   
56.
In many practical situations, order statistics arise naturally with random sample size. In this article, we review results on partial orderings and aging properties of such order statistics. The comparison of order statistics for different sample sizes is also discussed here.  相似文献   
57.
Proximity seeking is at the core of attachment theory. Previously proximity has been studied almost exclusively in psychological terms. In clinical practice, however, couple therapists may interpret physical distance between romantic partners as a marker for the quality of the attachment bond. Unfortunately, this concept of physical distance between partners as an expression of attachment has never been tested. This study examines whether physical distance between romantic partners is associated with attachment. In 53 students and 43 clinical couples physical distance was repeatedly measured from video using novel software with excellent reliability. Attachment was measured with the Experiences in Close Relationships questionnaire. It was found that male attachment anxiety about rejection repeatedly showed statistically significant associations with physical interpersonal distance in student and clinical couples. We conclude that attachment may manifest itself not only in terms of psychological intimacy but also in terms of physical distance. Clinical utility and research implications are discussed.  相似文献   
58.
Patterns of consumers' use of products are of interest to manufacturers. This paper is concerned with modelling diary data on the use of one product, shampoo, recorded to the nearest hour by over 500 men during 1 week. A binary response multilevel model is developed, building on similar models for consumer purchase data. The model allows for a dependence on the number of days since last use. The results of fitting various versions of this model are discussed. A problem is that the number of days since last use is missing for all times up to the first use. An approximate EM approach is considered to deal with this problem.  相似文献   
59.
The authors discuss a graph‐based approach for testing spatial point patterns. This approach falls under the category of data‐random graphs, which have been introduced and used for statistical pattern recognition in recent years. The authors address specifically the problem of testing complete spatial randomness against spatial patterns of segregation or association between two or more classes of points on the plane. To this end, they use a particular type of parameterized random digraph called a proximity catch digraph (PCD) which is based on relative positions of the data points from various classes. The statistic employed is the relative density of the PCD, which is a U‐statistic when scaled properly. The authors derive the limiting distribution of the relative density, using the standard asymptotic theory of U‐statistics. They evaluate the finite‐sample performance of their test statistic by Monte Carlo simulations and assess its asymptotic performance via Pitman's asymptotic efficiency, thereby yielding the optimal parameters for testing. They further stress that their methodology remains valid for data in higher dimensions.  相似文献   
60.
Record values can be viewed as order statistics from a sample whose size is determined by the values and the order of occurrence of observations. They are closely connected with the occurrence times of a corresponding non-homogenous Poisson process and reliability theory. In this paper, the information properties of record values are presented based on Shannon information. Several upper and lower bounds for the entropy of record values are obtained. It is shown that, the mutual information between record values is distribution free and is computable using the distribution of the record values of the sequence from the uniform distribution.  相似文献   
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