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81.
The mean residual life measures the expected remaining life of a subject who has survived up to a particular time. When survival time distribution is highly skewed or heavy tailed, the restricted mean residual life must be considered. In this paper, we propose an additive–multiplicative restricted mean residual life model to study the association between the restricted mean residual life function and potential regression covariates in the presence of right censoring. This model extends the proportional mean residual life model using an additive model as its covariate dependent baseline. For the suggested model, some covariate effects are allowed to be time‐varying. To estimate the model parameters, martingale estimating equations are developed, and the large sample properties of the resulting estimators are established. In addition, to assess the adequacy of the model, we investigate a goodness of fit test that is asymptotically justified. The proposed methodology is evaluated via simulation studies and further applied to a kidney cancer data set collected from a clinical trial.  相似文献   
82.
83.
The world is ageing both at an individual and a population level, and population ageing is truly a global phenomenon. Life expectancies at birth have increased at the global level from 47 years in the mid-20th century to around 70 years today, and are expected to rise to 76 years by the mid-21st century. The proportion of the world’s population aged 60 years and over has increased from 8 % in the mid-20th century to 12 %, and by 2050 it is expected to reach 21 %. The emergence of large numbers of centenarians has accompanied this development. This paper outlines this emergence historically and the likely growth in the number of centenarians in the 21st century, in particular in England and Wales, analysing mortality trends since 1840 and the rise in the number of centenarians in the 20th and 21st centuries. The number of centenarians in England and Wales increased from around 160 in 1922 to almost 12,500 by 2012, but if mortality at all ages had remained constant from 1912 to 2012, then by 2012 the number of centenarians would only have been around 720. By 2100, the number of centenarians is expected to reach around 1.4 million, but if future mortality at all ages were to remain constant, then by 2100 the number of centenarians would be around 78,000. However, if predicted mortality for those aged 55 years and over was to decrease by an additional 5 % every 5 years until 2100, then the number of centenarians in England and Wales would reach around 1.8 million by the end of the century.  相似文献   
84.
Land subsidence risk assessment (LSRA) is a multi‐attribute decision analysis (MADA) problem and is often characterized by both quantitative and qualitative attributes with various types of uncertainty. Therefore, the problem needs to be modeled and analyzed using methods that can handle uncertainty. In this article, we propose an integrated assessment model based on the evidential reasoning (ER) algorithm and fuzzy set theory. The assessment model is structured as a hierarchical framework that regards land subsidence risk as a composite of two key factors: hazard and vulnerability. These factors can be described by a set of basic indicators defined by assessment grades with attributes for transforming both numerical data and subjective judgments into a belief structure. The factor‐level attributes of hazard and vulnerability are combined using the ER algorithm, which is based on the information from a belief structure calculated by the Dempster‐Shafer (D‐S) theory, and a distributed fuzzy belief structure calculated by fuzzy set theory. The results from the combined algorithms yield distributed assessment grade matrices. The application of the model to the Xixi‐Chengnan area, China, illustrates its usefulness and validity for LSRA. The model utilizes a combination of all types of evidence, including all assessment information—quantitative or qualitative, complete or incomplete, and precise or imprecise—to provide assessment grades that define risk assessment on the basis of hazard and vulnerability. The results will enable risk managers to apply different risk prevention measures and mitigation planning based on the calculated risk states.  相似文献   
85.
Objective: To examine the perceptions among faculty and health professional students regarding mandatory vaccination policies on a health sciences campus. Participants: A total of 296 faculty and 244 students completed surveys during Fall 2015. Methods: The online survey administered to individuals who received the influenza vaccine during the fall 2015 influenza vaccination clinic season included five items evaluating perceptions of employer mandatory vaccination requirements. Results: Chi-square analysis indicated that although faculty and students agree mandatory vaccinations in a health care environment are appropriate, faculty are more likely than students to get vaccinated in the absence of a mandate. Additionally, a small fraction of faculty would consider employment elsewhere when facing this mandate. Conclusions: Overall, faculty and students had favorable perceptions about mandatory influenza vaccine policies. Since students were less likely to be vaccinated in the absence of a mandate, education of students should be improved to support the importance of vaccinations in a health care environment.  相似文献   
86.
Recently Beh and Farver investigated and evaluated three non‐iterative procedures for estimating the linear‐by‐linear parameter of an ordinal log‐linear model. The study demonstrated that these non‐iterative techniques provide estimates that are, for most types of contingency tables, statistically indistinguishable from estimates from Newton's unidimensional algorithm. Here we show how two of these techniques are related using the Box–Cox transformation. We also show that by using this transformation, accurate non‐iterative estimates are achievable even when a contingency table contains sampling zeros.  相似文献   
87.
This study examined the role of depressive symptoms, acute intoxication, and risk rationale in men’s use of condom use resistance (CUR) tactics in an experimental study. Participants included 313 heterosexual male, nonproblem drinkers, ages 21 to 30. Participants were randomized to one of four beverage conditions: no alcohol, placebo, low (.04%) alcohol dose, or high (.08%) alcohol dose. They read an eroticized scenario depicting a consensual sexual encounter with a female partner who requested a condom to prevent either pregnancy or sexually transmitted infections (STIs) (risk rationale) and then indicated their intentions to use 10 different CUR tactics. Hypotheses related to the pharmacological, dosage, and expectancy effects of alcohol were tested in a generalized linear model. In intoxicated (.04% and .08%) men who were given a pregnancy risk rationale, depressive symptoms were associated with stronger intentions to use CUR tactics than in sober (control and placebo) men. Men who received a high alcohol dose (.08%) and who were given a pregnancy risk rationale reported higher intentions to use CUR tactics than those who received a lower alcohol dose (.04%). Findings suggest that the pharmacological effects of alcohol on men’s likelihood to resist condoms vary by the saliency of the risk rationale and mood-related variables.  相似文献   
88.
Parody news programs regale viewers with satirical, witty, and humorous exposés of the political world and news coverage, but they have also been criticized for creating cynicism and political disengagement. This study found that parody news viewers are self-efficacious and more politically active than viewers of CNN, Fox News, MSNBC, or broadcast television news. Moreover, reliance on parody news shows does not lead to political polarization or government distrust.  相似文献   
89.
Theory and Society - This article argues that Orlando Patterson is a key contributor to postcolonial fiction and postcolonial theory as well as historical sociology and social theory, whose work...  相似文献   
90.
The Analysis of Verbal Behavior - Participants first became familiar with an image showing moderate symptoms of the skin cancer melanoma. In a generalization test, they indicated whether images...  相似文献   
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