Some Distributions on the Positive Real Line Which Have No Moments

A sharp upper bound is obtained for the difference of a pair of order statistics in terms of the sample standard deviation.     

A Note on the Relations Between Some Concepts of Positive Dependence

In this article, we provide some explicit examples showing that weak association in sequence is strictly weaker than weak association and strictly stronger than positive supermodular dependence. Furthermore, we show that strongly positive orthant dependence is strictly weaker than weakly association and strictly stronger than positive orthant dependence. Finally, we also show that positive supermodular dependence is not stronger than strongly positive orthant dependence.     

Tests of Symmetry in Three-dimensional Contingency Tables Based on Phi-divergence Statistics

In this paper we introduce a family of test statistics for testing complete symmetry in three-dimensional contingency tables based on phi- divergence families. These test statistics yield the likelihood ratio test and the Pearson test statistics as special cases. Asymptotic distribution for the new test statistics are derived under both the null and the alternative hypotheses. A simulation study is presented to show that some new statistics offer an attractive alternative to the classical Pearson and likelihood ratio test statistics for this problem of complete symmetry.     

Adaptive Deconvolution on the Non‐negative Real Line

In this paper, we consider the problem of adaptive density or survival function estimation in an additive model defined by Z=X+Y with X independent of Y, when both random variables are non‐negative. This model is relevant, for instance, in reliability fields where we are interested in the failure time of a certain material that cannot be isolated from the system it belongs. Our goal is to recover the distribution of X (density or survival function) through n observations of Z, assuming that the distribution of Y is known. This issue can be seen as the classical statistical problem of deconvolution that has been tackled in many cases using Fourier‐type approaches. Nonetheless, in the present case, the random variables have the particularity to be supported. Knowing that, we propose a new angle of attack by building a projection estimator with an appropriate Laguerre basis. We present upper bounds on the mean squared integrated risk of our density and survival function estimators. We then describe a non‐parametric data‐driven strategy for selecting a relevant projection space. The procedures are illustrated with simulated data and compared with the performances of a more classical deconvolution setting using a Fourier approach. Our procedure achieves faster convergence rates than Fourier methods for estimating these functions.     

A Simulation Study of Some Ridge Regression Estimators under Different Distributional Assumptions

Based on the work of Khalaf and Shukur (2005 Khalaf , G. , Shukur , G. ( 2005 ). Choosing ridge parameters for regression problems . Communications in Statistics – Theory and Methods 34 : 1177 – 1182 .[Taylor & Francis Online], [Web of Science ®] , [Google Scholar]), Alkhamisi et al. (2006 Alkhamisi , M. , Khalaf , G. , Shukur , G. ( 2006 ). Some modifications for choosing ridge parameters . Communications in Statistics – Theory and Methods 35 : 2005 – 2020 .[Taylor & Francis Online], [Web of Science ®] , [Google Scholar]), and Muniz et al. (2010 Muniz , G. , Kibria , B. M. G. , Shukur , G. ( 2010 ). On developing ridge regression parameters: a graphical Investigation. Submitted for Publication . [Google Scholar]), this article considers several estimators for estimating the ridge parameter k. This article differs from aforementioned articles in three ways: (1) Data are generated from Normal, Student's t, and F distributions with appropriate degrees of freedom; (2) The number of regressors considered are from 4–12 instead of 2–4, which are the usual practice; (3) Both mean square error (MSE) and prediction sum of square (PRESS) are considered as the performance criterion. A simulation study has been conducted to compare the performance of the estimators. Based on the simulation study we found that, increasing the correlation between the independent variables has negative effect on the MSE and PRESS. However, increasing the number of regressors has positive effect on MSE and PRESS. When the sample size increases the MSE decreases even when the correlation between the independent variables is large. It is interesting to note that the dominance pictures of the estimators are remained the same under both the MSE and PRESS criterion. However, the performance of the estimators depends on the choice of the assumption of the error distribution of the regression model.     

Some Results Based on a Version of the Generalized Dynamic Entropies

We propose new dynamic measures of uncertainty based on the notion of generalized dynamic entropy introduced in Di Crescenzo and Longobardi (2006). These can uniquely determine distribution functions in continuous and discrete cases, and the characterizations of some well-known distributions are provided. We also define some orderings and aging notions based on the generalized dynamic measures, and prove some of their properties, obtaining as corollaries results that have recently appeared in the literature.     

A further note on the bivariate normal distribution

It is indicated to what extent the conditional normality of the distribution of one comnonent of a bivariate random vector given the value of the other component together with a restricted type of conditional normality or the marginal normality for the other component is equivalent to the bivariate normality of this random vector.     

Some characterizations of multivariate distributions using products of the hazard gradient and mean residual life components

We give a general procedure to characterize multivariate distributions by using products of the hazard gradient and mean residual life components. This procedure is applied to characterize multivariate distributions as Gumbel exponential, Lomax, Burr, Pareto and generalized Pareto multivariate distributions. Our results extend the results of several authors and can be used to study how to extend univariate models to the multivariate set-up.     

基于网络搜索数据的住房价格预期与实际价格波动分析

在混频数据方法的框架下,分析网络搜索数据是否能够增强中国住房价格的解释能力。对2011年1月至2014年12月的时间序列数据分析显示:以房价为关键词得出的百度指数能够解释中国住房价格的部分波动,将其引入传统模型,显著增强了住房价格预测的准确性。研究表明:混频数据方法通过对高频网络搜索数据和低频官方统计数据进行整合,可以挖掘出大数据背后隐藏的丰富信息,为宏观和中观层面的研究提供坚实的微观数据基础。网络搜索数据提供了一个观察个体行为的良好途径,必将在未来促进宏观经济学到纳米经济学的深度融合。     

房地产业可持续发展指标研究

 房地产业可持续发展指标是指反映既能满足人们当前的住房需求,又不对人类后代满足其自身需求的能力造成危害的房地产业发展指标。它可以从环境领域、经济领域和社会生活三个方面进行研究。     

Some Early Work on the Duality Between Points and Lines

In this paper we will show that certain features of the type of duality recently discussed by Souvaine and Steele (1987) and Owen and Shiau (1988) may be traced in the earlier work of Laplace (1786), Newcomb (1873a, b) and Edgeworth (1888).     

渔业统计制度的国际比较及对我国的启示

随着全球经济一体化和信息技术的快速发展,我国的经济和贸易交往将进一步增强,社会经济现象将越来越复杂。因此,了解渔业统计制度并进行国际比较分析显得十分重要,它对国家制定渔业发展及经济管理政策有着重要意义。本文通过对各国渔业的统计制度和组织机构、统计法规和统计指标以及渔业统计管理和方法等方面的比较研究,为完善我国的渔业统计制度和运行机制提供借鉴。     

A Discrete Analog of the Generalized Exponential Distribution

In this article, we attempt to introduce a discrete analog of the generalized exponential distribution of Gupta and Kundu (1999 Gupta , R. D. and Kundu , D. ( 1999 ). Generalized exponential distributions . Austral. NZ J. Statist. 41 ( 2 ): 173 – 188 .[Crossref], [Web of Science ®] , [Google Scholar]). This new discrete generalized exponential (DGE(α, p)) distribution can be viewed as another generalization of the geometric distribution and it is more flexible in data modeling. We shall first study some basic distributional and moment properties of this family of new distributions. Then, we will reveal their structural properties and applications and also investigate estimation of their parameters. Finally, we shall discuss their convolution properties and arrive at some characterizations in the special cases DGE(2, p) and DGE(3, p).     

Some critical aspects of the use of exchangeability in statistics

Summary This expository paper provides a framework for analysing de Finetti's representation theorem for exchangeable finitely additive probabilities. Such an analysis is justified by reasoning of statistical nature, since it is shown that the abandonment of the axiom of σ-additivity has some noteworthy consequences on the common interpretation of the Bayesian paradigm. The usual (strong) fromulation of de Finetti's theorem is deduced from the finitely additive (weak) formulation, and it is used to solve the problem of stating the existence of a stochastic process, with given finite-dimensional probability distributions, whose sample paths are probability distributions. It is of importance, in particular, to specify prior distributions for nonparametric inferential problems in a Bayesian setting. Research partially supported by MPI (40% 1990, Gruppo Nazionale ?Modelli Probabilistici e Statistica Matematica?).     

基于混频数据的实体经济与金融市场时变溢出效应研究

本文基于混频VAR模型分析了中国实体经济与股票市场、债券市场之间的时变溢出效应。结果显示,实体经济与股票市场、债券市场之间收益率与波动率的溢出效应呈现显著的时变特征,溢出效应在金融危机期间呈现快速上升趋势,而后呈现下降态势,且易受到极端事件的影响;在大部分考察时期内存在股票市场向实体经济的波动率溢出效应,而债券市场相对于实体经济则从考察初期波动率溢出效应的净输入方转化为中后期的波动率溢出效应的净输出方。进一步分析收益率与波动率总溢出指数的影响因素,结果发现,极端事件、宏观经济代理变量和期限利差对于溢出效应具有正向影响,泰德利差对波动率总溢出指数具有负向影响,而投资者情绪指数对收益率总溢出指数具有负向影响。     

A characterization of probability distributions similar to the exponential

A concept of the lack-of-memory property at a given time point c > 0 is introduced. It is equivalent to the concept of the almost-lack-of-memory (ALM) property of the random variables. A representation theorem is given for the cumulative distribution function of such random variables as well as for corresponding decompositions in terms of independent random variables. It is shown that a periodic failure rate for a random variable is equivalent to the ALM property. In addition some properties of the service time of an unreliable server are observed.     

A Comparative Study of Some Modified Chi-Squared Tests

Some recent results in the theory and applications of modified chi-squared goodness-of-fit tests are briefly discussed. It seems that for the first time power of modified chi-squared type tests for the logistic and three-parameter Weibull distributions based on moment type estimators is studied. Power of different modified tests against some alternatives for equiprobable fixed or random grouping intervals, and for Neyman–Pearson classes is investigated. It is shown that power of test statistic essentially depends on the quantity of Fisher's sample information this statistic uses. Some recommendations on implementing modified chi-squared type tests are given.     

基于马尔柯夫模型的商品房价格波动研究

 已有的关于房地产价格的文献大部分是基于线性框架的。那么一个很及时的问题是：房地产价格是否表现出非线性的特点呢？我们利用基于非线性的马尔科夫机制转换模型对我国的房地产价格进行了研究。发现我国的房地产价格呈现出非线性的特点;马尔科夫机制转换模型的非线性估计很好地解释了我国房地产价格的特点;不同的状态具有不同的转换概率;两个状态分别具有2.2个季度和1.2个季度的持续期。     

基于马尔可夫域变模型的上海股市收益率非线性特征分析

针对股市收益率在不同时期内具有不同的均值、波动性和持续性等非线性特征,引入马尔可夫域变模型（MRSM）对上海股市收益率的均值与波动性的对应关系以及高、低收益率状态转换特征进行分析,结果表明马尔可夫域变模型与GARCH类模型相比较,显著地提高了对股票市场行为的描述能力。它不仅可以从动态角度明确刻画金融市场的“收益与风险”相对称的特征,而且可测定不同状态持续的可能性和由一种状态转向另一种状态的概率。