Methods for the estimation of failure distributions and rates from automobile warranty data

We consider the occurrence of warranty claims for automobiles when both age and mileage accumulation may affect failure. The presence of both age and mileage limits on warranties creates interesting problems for the analysis of failures. We propose a family of models that relates failure to time and mileage accumulation. Methods for fitting the models based on warranty data and supplementary information about mileage accumulation are presented and illustrated on some real data. The general problem of modelling failures in equipment when both time and usage are factors is discussed.     

《墨子》与中国小说

《墨子》是墨翟弟子或再传弟子记述墨子言行的集录。《墨子》一书虽然旨在反映墨家兼爱、非攻、尚贤、尚同等政治、社会主张,但以今天的小说观念观照《墨子》全书,其中的寓言故事、志怪传说、叙事写人等方面均与后世的小说文体有着千丝万缕的联系。研究《墨子》与小说文体的关系,无疑将进一步推动小说史研究的深入发展。     

民族传统体育项目现状与潜力分析

中华民族有着古老的文明史 ,民族传统体育有深厚的文化积淀 ,如何正确认识、挖掘、整理 ,是发展民族传统体育的关键所在。现有的民族传统体育项目在全民健身中的利用现状表明 ,中华民族传统体育是中国特色的全民健身体系的源泉 ,是学校教育改革与发展不可分割的组成部分 ,能带动中国经济的发展 ,具有不可低估的作用和潜力市场     

由《系年》第二章论郑国初年史事

清华简《系年》第二章记述西周覆灭,周室东迁的事迹,详读此章内容可知,《系年》作者心目中的郑国初年历史,大体与《郑语》《郑世家》等类同,而与《竹书纪年》佚文异说。     

左史、右史之名考辨

结合文献及考古资料,对长期以来争论不休的左史、右史问题再作考证,可以得出以下结论:左史、右史之名均出现于西周时期,从其职能以及当时人们的习惯来看,它并不是先秦时期的实有官制,应该是内史、太史的譬喻称呼。至于记言记事之职责,也并不特指左史、右史,而是针对先秦史官共有的职能而言。     

Insurance for low-probability hazards: A bimodal response to unlikely events

Two insurance experiments using real-money consequences and multiple rounds to provide experience are described. In the first experiment, subjects bid for insurance to prevent a fixed loss of 4 at probabilities ranging from .01 to .9. Mean bids were near expected value except at the lowest probability of.01, for which a very bimodal distribution was observed (some subjects bid zero and others bid much more than expected value). A second experiment explored this bimodality at a probability of .01 with loss increased to4 at probabilities ranging from .01 to .9. Mean bids were near expected value except at the lowest probability of.01, for which a very bimodal distribution was observed (some subjects bid zero and others bid much more than expected value). A second experiment explored this bimodality at a probability of .01 with loss increased to 40. A similar bimodal distribution was obtained that persisted over 50 rounds of experience. These laboratory results are consistent with field evidence for low-probability hazards, for which people appear either to dismiss the risks or to worry too much about them.We would like to thank Alan Carlin, Ann Fisher, Risa Palm, and David Brookshire for their helpful comments on an earlier version of this article, and Rebecca Boyce, Julie Irwin, Glenn Russell, and Joy Smith for research assistance. We also gratefully acknowledge support from the University of Colorado Council on Research and Creative Work for human subject payments and from the U.S. Environmental Protection Agency, Office of Policy, Planning and Evaluation for support for research design and analysis provided as part of Cooperative Agreement #CR812054. All errors, opinions and conclusions are the sole responsibility of the authors.     

Comparing the Survival of Two Groups with an Intermediate Clinical Event

Consider a subject entered on a clinicaltrial in which the major endpoint is a time metric such as deathor time to reach a well defined event. During the observationalperiod the subject may experience an intermediate clinical event.The intermediate clinical event may induce a change in the survivaldistribution. We consider models for the one and two sample problem.The model for the one sample problem enables one to test if theoccurrence of the intermediate event changed the survival distribution.This models provides a way of carrying out non-randomized clinicaltrial to determine if a therapy has benefit. The two sample problemconsiders testing if the probability distributions, with andwithout an intermediate event, are the same. Statistical testsare derived using a semi-Markov or a time dependent mixture model.Simulation studies are carried out to compare these new procedureswith the log rank, stratified log rank and landmark tests. Thenew tests appear to have uniformly greater power than these competitortests. The methods are applied to a randomized clinical trialcarried out by the Aids Clinical Trial Group (ACTG) which comparedlow versus high doses of zidovudine (AZT).     

环境群体事件:根源、遏制与杜绝简

近年来,环境群体事件的频发已经成为影响社会稳定的重要因素。本文从利益均衡与环境意识角度分析了环境群体事件发生的原因,得到的结论是由于社会公众的环境意识觉醒打破了地方政府与部分被规制企业之间的利益均衡,从而导致了环境群体事件的频发。在应对措施上,短期情况下应建立地方政府的环境业绩评价体系并加大社会公众对地方政府的环境监督,而在长期情况下应进行生态文明建设,彻底遏制环境群体事件的发生。     

Sexual Minority Women's Gender Identity and Expression: Challenges and Supports

Sexual minority women were divided into four groups to study their gender identities (butch and femme), and gender expression (traditionally gendered and non-traditionally gendered women who do not identify as butch or femme). Experiences of heterosexist events (discrimination, harassment, threats of violence, victimization, negative emotions associated with these events), mental health (self esteem, stress, depression), and supports for a sexual minority identity (social support, outness, internalized homophobia) were examined across these groups. Findings suggested that butch-identified women experienced more heterosexist events than femme women or women with non-traditional gender expressions. There were no differences in mental health variables.     

中国农村群体性事件的根源及其矫治

近几年来,中国农村群体性事件频繁发生,呈现出突发性、组织性、对抗性等特点,并且"由乡入城",严重影响了中国经济社会发展。农村群体性事件的发生,一方面反映了中国农民政治参与程度的提高;另一方面更反映了改革开放以来中国社会利益冲突的加剧与农民利益表达渠道的不畅,反映了政府公共服务职能的缺失与预警机制的不足。对农村群体性事件的矫治,应以社会公正为目标,改变社会利益格局,完善农民政治参与渠道,加快基层政府职能转变,健全农村群体性事件的预警机制。