60Co-r射线辐射保持系嘉浙B的M2代突变类型分析

用60 CO-r射线直接辐射保持系嘉浙B诱发突变 ,M2 代出现多种变异 ,按变异频率大小从高到底依次为 :叶色突变>早熟突变 >颖尖不退花突变 >高外露率突变 >薄颖壳突变 >花时早 >突变紫稃尖突变 >迟熟突变 ,上述 8个选择项的总突变频率达到 2 .4 19% ,说明辐射诱变改良保持系性状十分有效     

On the asymptotic normality of the L1- and L2-errors in histogram density estimation

The L₁ and L₂-errors of the histogram estimate of a density f from a sample X₁,X₂,…,Xn using a cubic partition are shown to be asymptotically normal without any unnecessary conditions imposed on the density f. The asymptotic variances are shown to depend on f only through the corresponding norm of f. From this follows the asymptotic null distribution of a goodness-of-fit test based on the total variation distance, introduced by Györfi and van der Meulen (1991). This note uses the idea of partial inversion for obtaining characteristic functions of conditional distributions, which goes back at least to Bartlett (1938).     

Generalized partially linear varying-coefficient models

Generalized varying-coefficient models are useful extensions of generalized linear models. They arise naturally when investigating how regression coefficients change over different groups characterized by certain covariates such as age. In this paper, we extend these models to generalized partially linear varying-coefficient models, in which some coefficients are constants and the others are functions of certain covariates. Procedures for estimating the linear and non-parametric parts are developed and their associated statistical properties are studied. The methods proposed are illustrated using some simulations and real data analysis.     

Estimating ordered parameters by linear programming

There are many models that require the estimation of a set of ordered parameters. For example, multivariate analysis of variance often is formulated as testing for the equality of the parameters versus an ordered alternative. This problem, referred to as isotonic inference, constrained inference, or isotonic regression, has led to the development of general solutions, not often easy to apply in special models. In this expository paper, we study the special case of a separable convex quadratic programming problem for which the optimality conditions lead to a readily solved linear complementarity problem in the Lagrange multipliers, and subsequently to an equivalent linear programming problem, whose solution can be used to recover the solution of the original isotonic problem. The method can be applied to estimating ordered correlations, ordered binomial probabilities, ordered Poisson parameters, ordered exponential scale parameters, or ordered risk differences.     

A simulation study of a discrete-time multiserver retrial queue with finite population

In this paper, we deal with a discrete-time multiserver retrial queue with finite population. Firstly, we study the Markov chain at the epochs immediately after slot boundaries making emphasis on the computation of its steady-state distribution. Then, the main performance measures are investigated. Besides, we simulate the waiting time of a customer in the retrial group under three different queueing policies. Some numerical examples are given to illustrate the analysis.     

Estimating the distribution function using k-tuple ranked set samples

The basic assumption underlying the concept of ranked set sampling is that actual measurement of units is expensive, whereas ranking is cheap. This may not be true in reality in certain cases where ranking may be moderately expensive. In such situations, based on total cost considerations, k-tuple ranked set sampling is known to be a viable alternative, where one selects k units (instead of one) from each ranked set. In this article, we consider estimation of the distribution function based on k-tuple ranked set samples when the cost of selecting and ranking units is not ignorable. We investigate estimation both in the balanced and unbalanced data case. Properties of the estimation procedure in the presence of ranking error are also investigated. Results of simulation studies as well as an application to a real data set are presented to illustrate some of the theoretical findings.     

Nonparametric estimation of the conditional distribution function in a semiparametric censorship model

In this paper we propose a new nonparametric estimator of the conditional distribution function under a semiparametric censorship model. We establish an asymptotic representation of the estimator as a sum of iid random variables, balanced by some kernel weights. This representation is used for obtaining large sample results such as the rate of uniform convergence of the estimator, or its limit distributional law. We prove that the new estimator outperforms the conditional Kaplan–Meier estimator for censored data, in the sense that it exhibits lower asymptotic variance. Illustration through real data analysis is provided.     

B股与H股及红筹股之间的溢出效应与信息流动

运用向量GARCH-M模型检验了B股与H股及红筹股之间的溢出效应与信息流动.实证结果表明:红筹股对沪深市B股、H股对沪市B股的收益和波动溢出效应均显著存在,而反向的溢出效应均不显著,表明信息是从红筹股向沪深市B股、从H股向沪市B股单向流动的;深市B股与H股之间相互的收益溢出效应均存在,而波动溢出效应均不存在,信息在H股和深市B股之间的流动情况不明显;在信息流动过程中,红筹股始终处于信息领先地位.     

丙硫咪唑驱绦虫试验

作者首次应用不同剂量的丙硫咪唑进行驱除建鲤绦虫试验。用丙硫咪唑20mg/Kg体重驱除建鲤肠道中的九江头槽绦虫,驱虫率达96.5％以上,效果好,安全可靠。     

关于有效促进社会公正的几个问题

本文认为:(1)为了顺利地推进改革,为了中国社会经济持续、有效和健康的发展,就必须适应新的历史条件,顺应民意、顺应现代社会的基本趋势,把社会公正放到一个突出的位置。(2)在中国现阶段应当开始建立一个初级的社会公平保障体系。初级社会公平保障体系的基本特征是低水准、广覆盖、有实效。对于国家来说,近期需要做的事情可以分为两大块,一是国家的直接投入,二是国家的立法、监督、执行和引导。(3)有一些根深蒂固的观念在妨碍着我们重视社会公正问题。这些观念主要包括:“原始积累不可避免”,“国家财力不足”,“重视公正便会妨碍效率”,因此我们必须对这些观念进行一番必要的反思。(4)要想构建一个公正而和谐的社会,就必须培育一个庞大的中等收入者人群,形成一个“两头小,中间大”的橄榄型的社会结构,那么社会就会变得越来越稳定了。