Geometric Anisotropic Spatial Point Pattern Analysis and Cox Processes

We consider spatial point processes with a pair correlation function, which depends only on the lag vector between a pair of points. Our interest is in statistical models with a special kind of ‘structured’ anisotropy: the pair correlation function is geometric anisotropic if it is elliptical but not spherical. In particular, we study Cox process models with an elliptical pair correlation function, including shot noise Cox processes and log Gaussian Cox processes, and we develop estimation procedures using summary statistics and Bayesian methods. Our methodology is illustrated on real and synthetic datasets of spatial point patterns.     

Estimating a frequency distribution when the sampling is biased

A simple random sample on a random variable A allows its density to be consistently estimated, by a histogram or preferably a kernel density estimate. When the sampling is biased towards certain x-values these methods instead estimate a weighted version of the density function. This article proposes a method for estimating both the density and the sampling bias simultaneously. The technique requires two independent samples and utilises ideas from mark-recapture experiments. An estimator of the size of the sampled population also follows simply from this density estimate.     

秦皇岛市高中生体育消费行为的调查

通过秦皇岛市5所高中621名学生的调查问卷，对高中生的体育消费行为进行调查。结果表明，秦皇岛市高中生体育消费的年级差异显著，在消费动机方面性别差异显著。高中生的体育消费受到家庭、学校、媒体信息等多种因素的影响。     

Density estimation using asymmetric kernels and Bayes bandwidths with censored data

We propose a modification to the regular kernel density estimation method that use asymmetric kernels to circumvent the spill over problem for densities with positive support. First a pivoting method is introduced for placement of the data relative to the kernel function. This yields a strongly consistent density estimator that integrates to one for each fixed bandwidth in contrast to most density estimators based on asymmetric kernels proposed in the literature. Then a data-driven Bayesian local bandwidth selection method is presented and lognormal, gamma, Weibull and inverse Gaussian kernels are discussed as useful special cases. Simulation results and a real-data example illustrate the advantages of the new methodology.     

Economic Viability Among Post-Retirement Aged Women

Longer life expectancy has increased concern about living standards among elder women. This paper examines the relation between labor market status and living standard post-retirement. We use data from two national surveys to contrast economic circumstances of post-retirement aged and currently employed women. Financial resources of aged women and factors associated with their magnitude are identified. We examine current economic resources and employee benefits of women who will retire after the year 2000. The paper concludes with a discussion of proactive mid-life strategies for long-term economic stability among women, with emphasis on unique concerns, of black women.     

不同种植密度下氮肥对马铃薯产量构成的影响

在大田栽培条件下，研究了不同的种植密度和施氮量对马铃薯的单株薯重、产量、块茎的淀粉含量和商品率的影响。结果表明：密度和施氮量分别为79500彬hm^2、225kg／hm^2时，单株薯重、产量、商品薯率达到最大值；畸病薯率随施氮量不同没有规率性变化；种植密度大，块茎的淀粉含量反而减小。     

Probability density function of quotient of order statistics from the pareto,power and weibull distributions

This paper deals with the probability density functions of quotient of order statistics. We use the Mellin transform technique, to find the distribution of the quotient Z= X/Xwhere X.,X(i < j) are the ith and jth order statistics from the Pareto, Power and Weibull distributions     

A class of distributions with the linear mean residual quantile function and it’s generalizations

In the present paper, we introduce and study a class of distributions that has the linear mean residual quantile function. Various distributional properties and reliability characteristics of the class are studied. Some characterizations of the class of distributions are presented. We then present generalizations of this class of distributions using the relationship between various quantile based reliability measures. The method of L-moments is employed to estimate parameters of the class of distributions. Finally, we apply the proposed class of distributions to a real data set.     

高中阶段普通教育与职业教育协调发展的对策

随着我国生产力发展水平的提高，高中阶段的教育规模也在不断扩大，但只有合理的教育结构才能与劳动力市场需求相适应。为此，通过对高中阶段普通教育与职业教育的结构分析，在职业教育普通化和普通教育职业化的发展趋势下，提出新时期职业教育与普通教育在价值观念层面上要保持一致，适当发展一定比例的综合高中，构建职、普沟通的立交桥，从而促进职、酱教育的协调发展。     

科技进步与北京社会阶层结构变动

自工业社会以来,科技进步引发深刻的社会阶层结构变动,改变着原有的社会分层体系。伴随着北京高新技术产业的发展,北京社会结构发生着深刻的变迁。研究表明,这一变迁突出表现在两方面:一方面,高新技术产业的发展,提高了劳动生产率,减少了劳动力投入,直接导致体力劳动者阶层在社会阶层结构中所占的比例规模不断减小,而脑力劳动者阶层规模不断壮大;另一方面,高新技术产业发展深刻影响着社会阶层结构中的资源配置,改变着原有的社会分层体系。