族群政治与东盟国家对不干预原则的选择性应用

如何解释东盟国家对不干预原则的选择性应用?对此已有研究提出了不同解释,然而,东南亚地区广泛存在的族群问题并没有得到充分重视。本文将族群冲突升级理论与东南亚的地区经验相结合,提出国内的族群政治竞争驱动东盟成员国干预其他成员国的族群冲突。已有理论认为,外部干预将破坏不干预等地区规范,同时也是族群冲突升级为国家间冲突的主要途径。本文则认为,干预行为对地区规范产生的影响,还取决于目标国的回应。目标国领导人的政治地位越稳固,该国越有可能接受其他国家善意的干预,相反,当领导人执政地位不稳时,目标国倾向于拒绝一切形式的外部干预。干预国与目标国之间不同的互动模式将导致三种不同的结果,即对不干预原则的"确认""破坏"以及"超越"。本文通过泰国—缅甸、马来西亚—泰国、马来西亚—菲律宾这三个"国家对"对理论框架进行验证。东盟成员国对不干预原则的选择性应用说明,这一规范的演变方向仍具有很强的不确定性。     

Limits of Applicability for the Deterministic Approximation of the Two-Step Clonal Expansion Model

Motivated by a hypothesis published recently, the limits of applicability of the deterministic approximation of the two-step clonal expansion model are investigated. The approximate hazard increases unlimited, while the exact hazard is approaching a constant value. The approximate solution becomes inapplicable for hazards in the order of that constant rate. When the initiation rate is much larger than the cell division rate, the survival rate is small when the approximation becomes inapplicable. The simplicity of the exact solutions suggests using them in all situations.     

冠姓、更名、改籍与民初旗民身份变化

作为一个特殊的社会群体，民初旗民在社会政治经济生活的诸多方面发生了深刻的变化。基于政治经济特权的丧失、社会地位和生活方式的变化以及平等的民族关系基本原则的确立等多种因素的影响，自民国成立后的多年间，各地屡有旗民申请冠姓、更名、改籍。对民初旗民冠姓、更名、改籍历史现象的考察，不仅有助于我们深刻了解转型时期旗民的生存状况，而且也有益于人们在社会发展和民族融合的视角下进一步认识和研究民初中国社会、政治、经济、思想文化、风俗习惯等诸多领域。     

Use of Cohort Information in the Design and Analysis of Case-Control Studies

Abstract.  Four case studies are presented to illustrate how information available on cohort members can be used to inform the control selection in epidemiologic case-control studies. The basic framework is the nested case-control paradigm and accompanying analysis methods. Emphasis is on development of intuition for choosing study design candidates, the form of the estimators, and extensions of the basic theory to solve design and analysis problems.     

Effect of frailty on marginal regression estimates in survival analysis

Unexplained heterogeneity in univariate survival data and association in multivariate survival can both be modelled by the inclusion of frailty effects. This paper investigates the consequences of ignoring frailty in analysis, fitting misspecified Cox proportional hazards models to the marginal distributions. Regression coefficients are biased towards 0 by an amount which depends in magnitude on the variability of the frailty terms and the form of frailty distribution. The bias is reduced when censoring is present. Fitted marginal survival curves can also differ substantially from the true marginals.     

解冻温度对牛颗粒冷冻精液品质影响的初步研究

取同一种公牛一次采精冷冻的颗粒精液进行不同温度的解冻试验，观察解冻温度对解冻精液品质的影响。实验结果证明，解冻温度对解冻后精子活力、畸形率和顶体完整率有显著性影响（P＜0．01），与精子活力和顶体完整率呈正相关（r值分别为0．83和0．94），与精子畸形率呈负相关（r值为－0．97）。解冻温度对解冻后精子存活时间无显著性影响（p＞0.05）。在本次实验中，解冻温度以65℃和75℃为最优，显著优于目前普遍采用的38—40℃。     

日本武士的生存土壤

武士的产生，有其深刻的经济、政治和军事动因。庄园制的兴起奠定了武士产生的经济基础，武力争夺土地的斗争造就了武士以武为本的生存土壤；各派政治势力争权夺势的政治斗争，为武士的产生和发展推波助澜，使武士的活动舞台从经济领域扩展到政治领域；中央集权常备兵制瓦解和军事力量虚弱化，军队无力履行国家政权支柱的职能，武士乘势蚕食其武力空间。武士适应武力争夺经济资源的需要而产生，以争夺财富和权力的武装斗争为生存土壤，以杀戮技能为生存资本，在征战杀伐中发展壮大。     

On a Bivariate Distribution with Exponential Marginals

A new bivariate distribution with exponential marginals has been introduced by Singpurwalla & Youngren (1993). This distribution is absolutely continuous and has a single parameter. It was originally motivated as the failure model for a two-component system experiencing damage described by a shot–noise process. The purpose of this paper is two-fold. The first is to articulate on several aspects of this distribution, in particular, its genesis, the nature of its dependence, its correlation structure, and its generalized version as a two-parameter bivariate distribution with exponential marginals. The second purpose of this paper is more general. Prompted by the need to explain certain features of the bivariate distribution, it is found useful to introduce a new notion in reliability and survival analysis. This notion is called the "hazard potential", of an item susceptible to failure. The hazard potential is viewed as a kind of hidden parameter of failure models that delineates a cause and effect relationship in reliability.     

Bayesian Semiparametric Cure Rate Model with an Unknown Threshold

Abstract.  We propose a Bayesian semiparametric model for survival data with a cure fraction. We explicitly consider a finite cure time in the model, which allows us to separate the cured and the uncured populations. We take a mixture prior of a Markov gamma process and a point mass at zero to model the baseline hazard rate function of the entire population. We focus on estimating the cure threshold after which subjects are considered cured. We can incorporate covariates through a structure similar to the proportional hazards model and allow the cure threshold also to depend on the covariates. For illustration, we undertake simulation studies and a full Bayesian analysis of a bone marrow transplant data set.     

Technological and Output Complementarities, and Inter-Firm Cooperation in Information Technology Ventures

Firms whose profiles of technologicalcompetence are complementary to one another are morelikely to enter into technology-based cooperativeagreements, and a broad level of technologicalcomplementarity is necessary for these agreements toextend as far as a mutual coordination of learningprocesses (combined research ventures). Using data onagreements between the world's largest firms in thearea of information technology (IT) and the patternsof technological specialization of these firms in theIT fields as revealed by their corporate patenting inthe US, we show that the technologicalco-specialization of firms helps to explain allianceformation, over and above the effects of anyco-specialization in IT products. While firms whosetechnological efforts are less complementary are lesslikely to cooperate for technology purposes, if theydo cooperate it is to exploit the differences in theirfields of expertise, and hence they are likely to usequasi-market organizational forms such as licensing,while the purpose of the alliance is restricted to anexchange of knowledge without any joint coordinationof learning (research). Instead, equity jointventures are likeliest when at a broad level ofaggregation the profiles of technologicalspecialization of partners are complementary, but ata more detailed level of disaggregation there is agreater distance between them, such that thecoordination of learning efforts is feasible, butrequires a stronger organizational commitment.