Joint impact of multiple observations on a subset of variables in multiple linear regression

In multiple linear regression analysis, each observation affects the fitted regression equation differently and has varying influences on the regression coefficients of the different variables. Chatterjee & Hadi (1988) have proposed some measures such as DSSE_ij (Impact on Residual Sum of Squares of simultaneously omitting the ith observation and the jth variable), F_j (Partial F-test for the jth variable) and F_j(i) (Partial F-test for the jth variable omitting the ith observation) to show the joint impact and the interrelationship that exists among a variable and an observation. In this paper we have proposed more extended form of those measures DSSE_IJ, F_J and F_J(I) to deal with the interrelationships that exist among the multiple observations and a subset of variables by monitoring the effects of the simultaneous omission of multiple variables and multiple observations.     

互联网信息服务业多元共治模式的作用机制研究——基于多参数影响的演化博弈视角

互联网信息服务业多元共治模式需要政府部门积极引导社会相关主体参与治理过程,若政府部门对协会与公众在治理过程中的作用条件认识不清,易导致片面追求二者的高参与度水平,难以实现多元共治模式的最大效用。本文考虑协会参与度、权力空间以及公众参与度、举报公正程度四个影响参数,运用博弈理论分析政府部门与互联网信息服务企业在治理过程中的行为策略演化过程,通过分析参数变动对系统稳定性的影响,探究有效发挥多元共治模式作用的条件。研究表明提高协会权利空间及公众举报公正程度有助于多元共治模式作用的发挥;公众举报存在失真情况时,政府自身监管能力的大小决定公众参与对治理效果的影响。     

“一核多元”型社区综合整治合作生产模式研究 ———以北京市 J 社区为例

老旧小区综合整治事关公众切身利益,体现国家服务效能与治理能力。 基于合作生产理论、公共价值和战略三角模 型间关系,从党建引领视角提出“一核多元”型综合整治合作生产模式。 以北京市 J 社区为例,采用张力分析工具,从使命管 理、政治管理与运营管理层面建构综合整治张力分析模型。 分析发现,党建引领的综合整治合作生产可促进社区合作生产网 络的形成与发展,这对社区治理模式创新与社区治理共同体建设具有重要意义。     

An analytic method for randomized trials with informative censoring: Part 1

Consider a randomized trial in which time to the occurrence of a particular disease, say pneumocystis pneumonia in an AIDS trial or breast cancer in a mammographic screening trial, is the failure time of primary interest. Suppose that time to disease is subject to informative censoring by the minimum of time to death, loss to and end of follow-up. In such a trial, the censoring time is observed for all study subjects, including failures. In the presence of informative censoring, it is not possible to consistently estimate the effect of treatment on time to disease without imposing additional non-identifiable assumptions. The goals of this paper are to specify two non-identifiable assumptions that allow one to test for and estimate an effect of treatment on time to disease in the presence of informative censoring. In a companion paper (Robins, 1995), we provide consistent and reasonably efficient semiparametric estimators for the treatment effect under these assumptions. In this paper we largely restrict attention to testing. We propose tests that, like standard weighted-log-rank tests, are asymptotically distribution-free -level tests under the null hypothesis of no causal effect of treatment on time to disease whenever the censoring and failure distributions are conditionally independent given treatment arm. However, our tests remain asymptotically distribution-free -level tests in the presence of informative censoring provided either of our assumptions are true. In contrast, a weighted log-rank test will be an -level test in the presence of informative censoring only if (1) one of our two non-identifiable assumptions hold, and (2) the distribution of time to censoring is the same in the two treatment arms. We also extend our methods to studies of the effect of a treatment on the evolution over time of the mean of a repeated measures outcome, such as CD-4 count.     

语言多属性决策的目标规划模型

研究了只有部分属性权重信息、属性值以语言变量或不确定语言变量形式给出且决策者对方案有偏好信息的语言多属性决策问题.给出了语言变量和不确定语言变量的运算法则,以及不确定语言变量之间比较的可能度公式,定义了语言变量的偏离度概念.在属性值以1)语言变量和2)不确定语言变量,这两种形式给出的情形下,分别建立了一个基于偏离度的目标规划模型,并通过求解这两种模型分别获得相应的属性权重.然后对于情形1),利用语言加权平均(LWA)算子,对语言决策信息进行加权集成,继而对方案进行排序和择优;对于情形2),利用不确定语言加权平均(ULWA)算子,对不确定语言决策信息进行加权集成,并利用可能度公式构造可能度矩阵(互补判断矩阵),继而利用互补判断矩阵排序公式对决策方案进行排序和择优.最后进行了实例分析.     

Accelerated life test sampling plans for the Weibull distribution under Type I progressive interval censoring with random removals

This paper considers the design of accelerated life test (ALT) sampling plans under Type I progressive interval censoring with random removals. We assume that the lifetime of products follows a Weibull distribution. Two levels of constant stress higher than the use condition are used. The sample size and the acceptability constant that satisfy given levels of producer's risk and consumer's risk are found. In particular, the optimal stress level and the allocation proportion are obtained by minimizing the generalized asymptotic variance of the maximum likelihood estimators of the model parameters. Furthermore, for validation purposes, a Monte Carlo simulation is conducted to assess the true probability of acceptance for the derived sampling plans.     

水平井分段多簇压裂缝间干扰研究

水平井分段多簇压裂在现场得到了广泛运用，其压裂过程中普遍存在缝间干扰现象。缝间干扰有助于形成复 杂裂缝网络以提高储层导流能力，但是也会导致起裂困难，甚至形成砂堵。因此有必要对分段多簇压裂的缝间干扰问 题进行研究。对此，基于弹性力学建立了分析多簇裂缝诱导应力的数学模型，从起裂压力、裂缝宽度、簇间距等多方面 研究了缝间干扰对水平井分段多簇压裂施工的影响。模拟结果显示，诱导应力会导致起裂压力升高、裂缝变窄，严重 时将造成压裂施工失败。通过进行分析，给出了起裂过程及延伸过程中缝间干扰的影响关系。分析认为，利用缝间干 扰提高改造体积时应当控制簇间距防止对压裂施工造成负面影响。研究结论对优化水平井分段多簇压裂设计具有指 导意义。     

An M/G/1 clearing queueing system with setup time and multiple vacations for an unreliable server

This paper studies an M/G/1 clearing queueing system with setup time and multiple vacations, in which all present customers in the system are served simultaneously and breakdowns may occur in busy or setup period. We investigate the stationary distribution of system size and the Laplace–Stieltjes transform of sojourn time. In addition, various performance measures are discussed, such as the mean system size at arbitrary time and the mean length of a vacation circle. Moreover, a cost analysis is carried out for this queueing system. Numerical results are presented to study the sensitivity of the system parameters on the expected cost function and system performances.     

国际组织与成员国法律责任多重归属问题研究

国际组织和成员国的法律责任归属问题一直以来都是国际法争论的话题。政府间国际组织作为一类国际法主体,应独立承担法律责任。但在实践中,成员国在执行国际组织决议的过程中往往滥用国际组织法律人格,其行为不仅是国际组织法律人格的体现,还代表了自己的意志,造成法律责任归属不明。以此种争议情形为研究对象,结合1999年的使用武力合法性案,2007年欧洲人权法院的拜拉米案和萨拉马提(Behrami/Saramati)案、阿尔吉达(Al-Jedda)案以及2014年海牙法院关于斯雷布雷尼察(Srebrenica)诉荷兰案的相关判决,借鉴国外学者近几年的相关研究,认为应当坚持国际组织和成员国法律责任的多重归属。围绕责任多重归属原则的确立过程,通过对2011年《国际组织责任条款草案》相关条文的分析,明确了行为归属与责任归属的关系:只有确定行为归属之后,才能确定责任归属;为了最终确定责任的多重归属,提出以有效控制为标准认定行为归属,并明确这种有效控制是对具体行为的事实控制。