A semiparametric additive rates model for recurrent event data

Recurrent event data often arise in biomedical studies, with examples including hospitalizations, infections, and treatment failures. In observational studies, it is often of interest to estimate the effects of covariates on the marginal recurrent event rate. The majority of existing rate regression methods assume multiplicative covariate effects. We propose a semiparametric model for the marginal recurrent event rate, wherein the covariates are assumed to add to the unspecified baseline rate. Covariate effects are summarized by rate differences, meaning that the absolute effect on the rate function can be determined from the regression coefficient alone. We describe modifications of the proposed method to accommodate a terminating event (e.g., death). Proposed estimators of the regression parameters and baseline rate are shown to be consistent and asymptotically Gaussian. Simulation studies demonstrate that the asymptotic approximations are accurate in finite samples. The proposed methods are applied to a state-wide kidney transplant data set.     

ESTIMATION OF PARAMETERS IN THE MARGINAL FISHER DISTRIBUTION1

The Fisher distribution is frequently used as a model for the probability distribution of directional data, which may be specified either in terms of unit vectors or angular co-ordinates (co-latitude and azimuth). If, in practical situations, only the co-latitudes can be observed, the available data must be regarded as a sample from the corresponding marginal distribution. This paper discusses the estimation by Maximum Likelihood (ML) and the Method of Moments of the two parameters of this marginal Fisher distribution. The moment estimators are generally simpler to compute than the ML estimators, and have high asymptotic efficiency.     

穆勒女性主义思想评析

穆勒的女性主义思想一方面强调两性享有平等的政治权、经济权、教育权,另一方面肯定社会分工领域女性的从属地位,并以男女的同一性来论证男女平等,忽视妇女自身的特点和优势.     

A class of accelerated means regression models for recurrent event data

In this article, we propose a general class of accelerated means regression models for recurrent event data. The class includes the proportional means model, the accelerated failure time model and the accelerated rates model as special cases. The new model offers great flexibility in formulating the effects of covariates on the mean functions of counting processes while leaving the stochastic structure completely unspecified. For the inference on the model parameters, estimating equation approaches are developed and both large and final sample properties of the proposed estimators are established. In addition, some graphical and numerical procedures are presented for model checking. An illustration with multiple-infection data from a clinic study on chronic granulomatous disease is also provided.     

Understanding Public Perceptions of Benefits and Risks of Childhood Vaccinations in the United States

In the face of a growing public health concern accompanying the reemerging threat of preventable diseases, this research seeks mainly to explain variations in the perceived benefits and risks of vaccinations among the general public in the United States. As Mary Douglas and Aaron Wildavsky's grid‐group cultural theory of risk perception claims, the analytical results based upon original data from a nationwide Internet survey of 1,213 American adults conducted in 2010 suggest that individuals’ cultural predispositions contribute to the formation of their perceptions pertaining to vaccine benefits and risks at both societal and individual levels, in conjunction with other factors suggested by previous risk perception literature, such as perceived prevalence of diseases, trust, knowledge level, and demographic characteristics. Those with a strong hierarch orientation tend to envision greater benefits and lesser risks and conceive of a relatively high ratio of benefit to risk when compared to other cultural types. By contrast, those with a strong fatalist tendency are inclined to emphasize risks and downplay benefits while conceiving of a low vaccination benefit‐risk ratio. Situated between hierarchs and fatalists, strong egalitarians are prone to perceive greater benefits, smaller risks, and a more positive benefit‐risk ratio than strong individualists.     

人力资本与企业发展

本文在分析了人力资本的特征和形成以及我国企业人力资本现状的基础上,认为企业应在建立人力资本的激励约束机制、营造优秀的企业文化、进行人力资本的投资和进行人力资本的积蓄四个方面采取相应的措施。     

The Benefits and Costs of Using Metadata to Improve Enterprise Document Search

The literature shows that there are many problems with enterprise document search. Studies reveal that typical knowledge workers spend between 10% and 20% of their time searching for documents they never find. While many argue that metadata can improve enterprise document search, in reality few organizations use metadata. This represents a missed opportunity. This article describes the results of two experiments that use simulation to evaluate the actual impact of metadata on the costs and benefits of enterprise search. The first study provides quantitative evidence of the increase in recall and precision that stems from the use of metadata‐enhanced document searches. The second study demonstrates that simple metadata structures can be nearly as effective as complex ones, implying that the cost of creating and maintaining metadata is likely to be lower than generally thought. This is the first study to provide explicit quantitative evidence of the gains that can be achieved from the use of metadata, and one of only a handful of studies that examines the cost of creating and maintaining metadata.     

精英利益均衡与农村合作经济组织发展

以当代乡村精英研究中的体制内外精英的划分为视角,考察了陕西省W村草莓协会的成立过程与发展现状,认为在多数的中西部村庄中精英利益的均衡是农村合作经济组织发展的重要保证,其发展困境也是由精英利益失衡造成的。并在分析的基础上提出了均衡精英利益、政府介入、提升农民合作意识、培养人才等政策建议。     

马克思恩格斯利益机制思想及其当代价值

马克思恩格斯利益机制包括利益主体、利益客体和利益实现的手段三要素,三要素遵循其固有的规律相互影响,完成利益主体对利益客体的历史性诉求,最终达到利益主体的历史性解放。现实的个人是利益机制的利益主体的逻辑起点,物质生活条件是利益客体的初始范畴,生产是利益机制的实现手段。马克思恩格斯利益机制思想闪现历史与逻辑相统一的方法论光芒,是解决我国现时代利益问题的一种有效方式和方法。     

“诺布效应”的逻辑与超越

在哲学实验中著名的“诺布效应”,基于道德判断天然地遵守着一种贸易特征的机制和原则：以收益最大化的个体愿望,达成与他人的等价交换,或者说,以与他人的等价交换,实现个体收益的最大化。它彰显出社会行为中的利己主义,以及否定和扬弃利己主义的努力,正是二者的冲突与对话,实现了利己主义与利他主义的平衡,达成了个体与社会的契约,使社会成为可能。利己主义的超越,意味着人在努力摆脱自然的束缚,获得更多的自由,实现更大程度的解放。