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81.
Estimated associations between an outcome variable and misclassified covariates tend to be biased when the methods of estimation that ignore the classification error are applied. Available methods to account for misclassification often require the use of a validation sample (i.e. a gold standard). In practice, however, such a gold standard may be unavailable or impractical. We propose a Bayesian approach to adjust for misclassification in a binary covariate in the random effect logistic model when a gold standard is not available. This Markov Chain Monte Carlo (MCMC) approach uses two imperfect measures of a dichotomous exposure under the assumptions of conditional independence and non-differential misclassification. A simulated numerical example and a real clinical example are given to illustrate the proposed approach. Our results suggest that the estimated log odds of inpatient care and the corresponding standard deviation are much larger in our proposed method compared with the models ignoring misclassification. Ignoring misclassification produces downwardly biased estimates and underestimate uncertainty. 相似文献
82.
Professor Stephen Senn Dr Dipti Amin Professor Rosemary A. Bailey Professor Sheila M. Bird FFPH Dr Barbara Bogacka Mr Peter Colman Dr rew Garrett Professor rew Grieve Professor Sir Peter Lachmann FRS FMedSci 《Journal of the Royal Statistical Society. Series A, (Statistics in Society)》2007,170(3):517-579
83.
84.
Has the image of Che Guevara lost its power to evoke radical politics in the face of pervasive commodification? The commercialization of this 1960s political icon has called into question the power of the market to shape collective memories. Meanwhile, antisystemic movements of the left continue to erect his image at protest events. In light of this contest over how Che Guevara is remembered, we investigate, using data from a survey of Spanish citizens, who is most likely to recall him. We find qualified support for the theory of generational imprinting—Che is more often recalled by those generations who saw him rise to prominence during their formative years, although prominent as a collective symbol rather than as a living person. Our results also corroborate the claim that historical figures or events are more salient for, and therefore more likely to be remembered by, some subgenerational units than others. Thus, although the younger generations are in general more likely than their elders to recall Che, he is most frequently remembered by the highly educated leftists who espouse postmaterialist and posttraditionalist values and identify more with their local regions than with the nation of Spain. These patterns suggest that, in contrast to the dire predictions of mass culture theorists, the memory of Che Guevara has become increasingly tied to markers of social, ethnic‐regional, and political identity. 相似文献
85.
Maximum likelihood estimation and goodness-of-fit techniques are used within a competing risks framework to obtain maximum likelihood estimates of hazard, density, and survivor functions for randomly right-censored variables. Goodness-of- fit techniques are used to fit distributions to the crude lifetimes, which are used to obtain an estimate of the hazard function, which, in turn, is used to construct the survivor and density functions of the net lifetime of the variable of interest. If only one of the crude lifetimes can be adequately characterized by a parametric model, then semi-parametric estimates may be obtained using a maximum likelihood estimate of one crude lifetime and the empirical distribution function of the other. Simulation studies show that the survivor function estimates from crude lifetimes compare favourably with those given by the product-limit estimator when crude lifetimes are chosen correctly. Other advantages are discussed. 相似文献
86.
For a wide variety of applications, experiments are based on units ordered over time or space. Models for these experiments generally may include one or more of: correlations, systematic trends, carryover effects and interference effects. Since the standard optimal block designs may not be efficient in these situations, orthogonal arrays of type I and type II, which were introduced in 1961 by C.R. Rao [Combinatorial arrangements analogous to orthogonal arrays, Sankhya A 23 (1961) 283–286], have been recently used to construct optimal and efficient designs for many of these experiments. Results in this area are unified and the salient features are outlined. 相似文献
87.
职业地位取得的社会性别差异 总被引:6,自引:0,他引:6
本文从描述被调查夫妇之间职业流动的性别差异出发,分别勾画出他们的地位实现模型。首先验证了不论性别,教育地位都是决定职业地位实现的首要变量;但也正是在教育地位的实现和向上流动(再求学)中,伴随婚姻生育等生命事件的发生,无形的结构性制度因素(意识形态层面的性别制度、性别规范和性别文化)正如后现代主义试图解构的那样依然支配着性别角色的社会化和继续社会化,使扮演双重角色的妻子或无意识地或有意识地遭遇了丈夫不为之所累的两难困境,并最终阻碍了女性的教育地位、既而是职业地位的实现。本文最后提出了三点建议和几个尚待解决的问题。 相似文献
88.
体育场馆融资模式选择框架研究 总被引:2,自引:0,他引:2
我国传统的体育场馆建设融资模式存在建设资金有限、赛后经营困难、管理效率低等问题,已不能适应体育场馆的建设需要,迫切需要引入新的融资模式。BOT(Built-Operation-Transfer)、PPP(Public-Private-Partnership)等融资模式在国外体育场馆融资中得到了广泛应用,对我国体育场馆融资模式的更新和多样化有积极的意义。从融资难度、风险分配等方面比较各种融资模式的特点,分析了体育场馆准公共产品特点对融资模式选择的影响,提出了基于场馆类型、场馆重要程度、融资和经营难度与期望目标四维的体育场馆融资模式选择框架模型。 相似文献
89.
John Bynner Heather Joshi 《Innovation: The European Journal of Social Science Research》2007,20(2):159-179
Survey data from cross-sectional snapshots give an incomplete picture of the social fabric. Without longitudinal information, planners, practitioners, social scientists and policy makers would be in the dark about dynamics, durations and pathways of human development. Longitudinal data collected in birth cohort studies give a better guide to long-term processes and outcomes and are more informative about the causal relations that are the drivers of disadvantage or success. The content and structure of Britain's Birth Cohort Studies are described to illustrate the challenges of creating and studying longitudinal evidence. Examples of findings and policies based on these prospective longitudinal studies are given, along with a discussion of the practical decisions that have to be confronted in undertaking them. 相似文献
90.
Stephanie M. Pickle Timothy J. Robinson Jeffrey B. Birch Christine M. Anderson-Cook 《Journal of statistical planning and inference》2008
Parameter design or robust parameter design (RPD) is an engineering methodology intended as a cost-effective approach for improving the quality of products and processes. The goal of parameter design is to choose the levels of the control variables that optimize a defined quality characteristic. An essential component of RPD involves the assumption of well estimated models for the process mean and variance. Traditionally, the modeling of the mean and variance has been done parametrically. It is often the case, particularly when modeling the variance, that nonparametric techniques are more appropriate due to the nature of the curvature in the underlying function. Most response surface experiments involve sparse data. In sparse data situations with unusual curvature in the underlying function, nonparametric techniques often result in estimates with problematic variation whereas their parametric counterparts may result in estimates with problematic bias. We propose the use of semi-parametric modeling within the robust design setting, combining parametric and nonparametric functions to improve the quality of both mean and variance model estimation. The proposed method will be illustrated with an example and simulations. 相似文献