Extreme value models with application to drought data

Summary The exact distributions of the productXY are derived whenX andY are independent random variables and come from the extreme value distribution of Type I, the extreme value distribution of Type II or the extreme value distribution of Type III. Of the, six possible combinations, only three yield closed-form expressions for the distribution ofXY. A detailed application of the results is provided to drought data from Nebraska. The author would like to thank the referees and the Associate Editor for carefully reading the paper and for their great help in improving the paper.     

中共三代领导人对社会主义民主实现途径的探索

没有民主就没有社会主义,就没有社会主义现代化。就社会主义民主来说,选择其实现的正确途径具有重要意义。中国共产党三代领导人对此问题给予了高度的重视,并进行了积极的探索。毛泽东选择了自下而上的群众政治运动式的"大民主";邓小平强调建立健全民主制度,将民主与法制视为不可或缺、相互依存的两方面;江泽民将"法治"作为执政党治国理念和基本方略,制定出具体的民主政治建设的基本纲领和措施。社会主义民主在三代领导人的不懈探索与实践中不断向前推进。     

一种多波形雷达信号全数字产生及处理系统

提出并实现了兼容多种雷达脉压信号的全数字产生及处理系统。其信号包括线性调频信号、非线性调频信号及其多相码、泰勒（Ｔａｙｌｏｒ）四相码信号等。利用级联型ＦＩＲ滤波器ＩＭＳＡ１００组成数字复相关脉压网络对多种带宽（带发达５ＭＨｚ）脉压信号进行实时数字处理；分析了数字方法运用于波形合成中由于ＤＡＣ零阶保持特性造成的信号频谱高频失真的机理；采用提高ＤＡＣ转换速率以获得近似理想冲激串取样的方法，产生了多种性能稳定、波形质量高的宽带雷达脉压信号。文中给出了部分模拟与实验结果。     

Introduction Private and Public: Gender,Generation and Family Life in Flux

In the past four decades, Hong Kong has seen a dramatic transformation of the social location of women in the public sphere, with deep and far-reaching ramifications for courtship, marriage, fertility, conceptions of parenthood, familial power, and equality and freedom. A sociology of the family is thus by necessity a sociology of women in particular, and of gender relations in general. Indeed, recent developments in research on marriage and the family in Hong Kong reflect this new awareness. Using rigorous sociological frameworks, this new line of research has begun to meet with some success in analyzing contemporary social issues that are prominent in the public consciousness. This essay reviews studies of four topical areas: determinants of the postponement of first marriage among women, the effect of live-in foreign domestic workers on family dynamics, violence against women and children in the family, and the livelihood strategies of cross-border families. These studies have attempted to integrate the interplay of the impact of a changing economy and society on the family and the role played by women in the family. The resulting dynamic interactions amongst the members within the family and the changes they bring about become propellants for change in the economy and society and pose new challenges. The family is indeed a troubled institution. It is so because myriad public issues are being taken on, confronted, worked through, and acted out within the family. The agony, and indeed the ecstasy, of the family is a reflection of the success, and failure, of society.     

Bayesian Survival Analysis Using Bernstein Polynomials

Abstract.  Bayesian survival analysis of right-censored survival data is studied using priors on Bernstein polynomials and Markov chain Monte Carlo methods. These priors easily take into consideration geometric information like convexity or initial guess on the cumulative hazard functions, select only smooth functions, can have large enough support, and can be easily specified and generated. Certain frequentist asymptotic properties of the posterior distribution are established. Simulation studies indicate that these Bayes methods are quite satisfactory.     

三维涡流场基于有限元法的电磁位对

介绍了用有限元法解决三维涡流场问题时电磁位对的优选问题,分析了其适应情况和优缺点.对目前基于有限元法的三维涡流场数值分析方法的国内外现状作了综合评述.     

Non-parametric recursive estimates of a probability density function and its derivatives

Recursive estimates of a probability density function (pdf) are known. This paper presents recursive estimates of a derivative of any desired order of a pdf. Let f be a pdf on the real line and p?0 be any desired integer. Based on a random sample of size n from f, estimators f^(p)_n of f^(p), the pth order derivatives of f, are exhibited. These estimators are of the form $\text{n}{}^{\mathrm{?1}}\text{∑n}\text{j=1}\text{δ}{}_{\mathrm{jp}}$, where δ_jp depends only on p and the jth observation in the sample, and hence can be computed recursively as the sample size increases. These estimators are shown to be asymptotically unbiased, mean square consistent and strongly consistent, both at a point and uniformly on the real line. For pointwise properties, the conditions on f^(p) have been weakened with a little stronger assumption on the kernel function.     

Limit theorems for a general weighted process under random censoring

Necessary and sufficient conditions for weak and strong convergence are derived for the weighted version of a general process under random censoring. To be more explicit, this means that for this process complete analogues are obtained of the Chibisov-O'Reilly theorem, the Lai-Wellner Glivenko-Cantelli theorem, and the James law of the iterated logarithm for the empirical process. The process contains as special cases the so-called basic martingale, the empirical cumulative hazard process, and the product-limit process. As a tool we derive a Kiefer-process-type approximation of our process, which may be of independent interest.     

On random variate generation for the generalized hyperbolic secant distributions

We give random variate generators for the generalized hyperbolic secant distribution and related families such as Morris's skewed generalized hyperbolic secant family and a family introduced by Laha and Lukacs. The rejection method generators are uniformly fast over the parameter space and are based upon a complex function representation of the distributions due to Harkness and HarknessThe author's research was sponsored by NSERC Grant A3456 and FCAR Grant 90-ER-0291.     

A review on strong convergence of weighted sums of random elements based on Wasserstein metrics

In a previous paper the authors proposed a simple method to extend results about almost sure convergence for weighted sums of real random variables to the case of Banach-valued random elements. The method arises from the extension of Skorohod's Representation Theorem for weakly convergent sequences due to Blackwell and Dubins, applied to the general framework of weakly equivalent tight sequences of probability measures. This provides a scheme which permits us to handle separately a problem that behaves like the Glivenko-Cantelli Theorem and a question on uniform integrability which generally is reduced to the real valued version of the general problem to be solved.

In this paper we prove that Wasserstein's metrics can play the same role as Skorohod's Representation Theorem in the preceding scheme. We also show that our method can be applied to obtain results with respect to various summability methods (Abel, Euler, …) even in the case in which the ‘weights’ are linear operators.