Discrete‐time survival trees

Tree‐based methods are frequently used in studies with censored survival time. Their structure and ease of interpretability make them useful to identify prognostic factors and to predict conditional survival probabilities given an individual's covariates. The existing methods are tailor‐made to deal with a survival time variable that is measured continuously. However, survival variables measured on a discrete scale are often encountered in practice. The authors propose a new tree construction method specifically adapted to such discrete‐time survival variables. The splitting procedure can be seen as an extension, to the case of right‐censored data, of the entropy criterion for a categorical outcome. The selection of the final tree is made through a pruning algorithm combined with a bootstrap correction. The authors also present a simple way of potentially improving the predictive performance of a single tree through bagging. A simulation study shows that single trees and bagged‐trees perform well compared to a parametric model. A real data example investigating the usefulness of personality dimensions in predicting early onset of cigarette smoking is presented. The Canadian Journal of Statistics 37: 17‐32; 2009 © 2009 Statistical Society of Canada     

Asymptotic properties of nonparametric M-estimation for mixing functional data

We investigate the asymptotic behavior of a nonparametric M-estimator of a regression function for stationary dependent processes, where the explanatory variables take values in some abstract functional space. Under some regularity conditions, we give the weak and strong consistency of the estimator as well as its asymptotic normality. We also give two examples of functional processes that satisfy the mixing conditions assumed in this paper. Furthermore, a simulated example is presented to examine the finite sample performance of the proposed estimator.     

结构现实主义理论的科学主义倾向分析

“科学主义”概念主要指仿照自然科学的程序来构建理论。结构现实主义在理论构建过程中表现出了强烈的科学主义倾向,尤其体现在其研究假设中。沃尔兹的科学主义倾向存在一定的局限性,但总体而言,其理论还是较好地满足了科学主义的要求,这种构建理论的方式有着重大意义,它对整个西方国际关系理论的发展都具有深远影响。     

Απόλιδας: an analysis of the international legal framework in the field of statelessness and the U.N.H.C.R.’s communication campaign

In her The Origins of Totalitarianism, Hannah Arendt described the condition of apolidia (statelessness) – through words that still resonate today – as that of persons who have lost their rights because they have fled their homeland. According to the Office of the United Nations High Commissioner for Refugees (U.N.H.C.R.), there are about 10 million stateless persons worldwide, 600,000 of whom live in the European Union (E.U.). It seems impossible to imagine the concept of statelessness, which although it has a very specific definition in international law, remains a vague notion for the intellect and common sense. This paper will firstly focus on the historical evolution of the concept of nationality under international law. Secondly, it will deal with the international legal framework, and in particular the 1954 and 1961 Conventions on the improvement of the conditions of stateless persons and the prevention of statelessness. It will then turn to the U.N.H.C.R.’s mandate in relation to statelessness, and how this organization contributes to the promotion of an effective right to nationality. Finally, U.N.H.C.R.'s communication campaigns to end statelessness will be analyzed, in order to stress the positive impact of an effective communication strategy.     

菲骈吲哚里西定生物碱的分离与化学结构鉴定

以生测活性跟踪牛心朴子草地上部分醇浸膏中抗烟草花叶病毒 (TMV)有效组份的化学分离 ,经凝胶色谱、硅胶柱层析等液液分离得到三个纯物质 .经理化常数、波谱分析与文献对照 ,鉴定它们是菲骈吲哚里西定生物碱 ,包括 (1 ) 7-脱甲氧基娃儿藤碱 .(2 ) N-氧化 -7-脱甲氧基娃儿滕碱 .(3 )娃儿藤硅 .它们是已知化合物 ,但由牛心朴子草分离得到 (2 )是首次报导 .     

华中抗日根据地灾荒救济工作研究

新四军所在的华中抗日根据地是一个自然灾害频发的地区,根据地政府采取了一系列救灾救荒的措施,如兴修水利、鼓励垦荒、赈济灾民、发放贷款、提倡互助、减免税收、扑灭蝗虫等。华中抗日根据地灾荒救济工作的特点是：政府救济与民间救济相结合,未雨绸缪,防患于未然,重视工作效率与工程质量,鼓励生产自救。华中抗日根据地灾荒救济政策的推行,保证了根据地群众生命财产的安全,改善了灾区群众的生活,密切了军民关系,巩固了根据地政权．     

青少年流行语中的"N"

“N”是近年来在青少年群体中高频出现的一个新词,其用法相当于数词(或数量形容词)和程度副词。通过超常变异的形式表达了强烈的主观情态,体现了“极量”的语义特征,以“N”为代表的青少年流行语在表述数量多少、级别差异和程度高低时,总是通过现有语言体系中某些词语的“移位”、不同认知范畴符号的“移域”或从不同语言体系引介形成的“占位”来构建新的表述体系,显现出模糊性、形象性、多变性特征。     

Pay premiums for economic sector and race: A decomposition

This paper examines two issues concerning a dual economy theory of labor markets. Using data from the older men's file of the National Longitudinal Surveys, I first investigate the degree to which differences in rates of pay among economic sectors (competitive, monopoly, public) are accounted for by sector differences in (1) human capital composition, (2) unionization, (3) occupational skill requirements, and (4) other factors producing an ability and willingness to pay high wages. The results of this decomposition suggest that the greater ability and willingness to pay high wages and the higher levels of unionization are the primary factors producing a monopoly sector pay premium. Second, I examine how racial differences in pay vary across sector and perform an analogous decomposition of these differences. In contrast to several previous studies, the relative disadvantages of black men were found to be somewhat greater in the competitive sector than in the monopoly sector.     

论汉语构词法之“N ＋X”组合

一种大量存在于上古汉语词汇中的“大名冠小名”偏正结构的主要组合特点为前语素是事物类名，后语素是其下位小名。根据原型论对这一独特构词法“N＋X”式的内部组合特征的深层分析和历时发展状况的研究表明，认为其在秦汉后就丧失生命力而消亡的观点有待商榷。     

THE EFFECT OF JOINT CUSTODY ON FAMILY OUTCOMES

Since the 1970s almost all US states have introduced a form of joint custody after divorce. I analyze the causal effect of these custody law reforms on different family outcomes. My identification strategy exploits the different timing of reforms across the US states. Estimations based on state panel data suggest that the introduction of joint custody led to an increase in marriage rates, an increase in overall fertility (including a shift from nonmarital to marital fertility), and an increase in divorce rates for older couples. Accordingly, female labor market participation decreased. Further, male suicide rates and domestic violence fell in treated states. The empirical evidence is consistent with the hypothesis that joint custody increased the relative bargaining power of men within marriage.