中国女子中长跑运动成绩增长规律的灰色模型及其预测

本文应用灰色系统理论和方法，以历年度中国女子中长跑运动各项前１０名成绩为数据数列，对中国女子中长跑运动成绩增长规律进行了分析，并对到２０００年中国女子中长跑运动成绩的发展趋势进行了预测．     

山东省制造业人力资源需求量预测与分析

山东是我国的制造业大省,要实现制造业从"制造"到"创造"的跨越,人力资源的支持必不可少。通过对山东省制造业人力资源需求现状的概括分析,综合运用一元回归预测模型、多元回归预测模型、时变增长率预测模型和人力资源需求弹性系数模型预测未来山东省制造业人力资源需求的数量、质量和结构,并对山东省制造业人力资源需求预测结果的可行性进行分析,以期对山东省政府构建制造业人力资源战略和产业发展战略起到一定的借鉴意义。     

基于误差校正的ARMA-GARCH股票价格预测

针对时间序列预测和简单回归预测各自的侧重点不同,综合两者优点,对股票价格进行预测。首先将股价数据转换成对数收益率,利用ARMA-GARCH模型对收益率序列建立模型,对上证指数股票价格进行初步预测;然后建立回归模型对GARCH模型误差中未被解释的成分进行分析和拟合,利用回归模型预测的误差对GARCH模型预测结果进行校正。在选择回归模型变量时,引入变量间的相关性分析筛选合适的影响因子,利用主成分分析方法提取影响因子中包含的信息,实现对解释变量的降维,获取具有代表性的综合指标,以提高建模精度。实例研究证明该方法对于上证指数股票价格预测较为准确。     

基于小波方法的企业发展水平预测

通过对企业单一指标进行选取、量化、标准化与合成处理,建立了企业发展水平指标,并利用小波方法对企业发展水平进行了分析和预测,得到了较好的效果,同时通过大量的研究试算,预测了某具体企业的企业发展水平。     

Consistent Estimation of the Regression Coefficient Through Weighted Arithmetic Mean of the Inconsistent Estimators in Replicated Ultrastructural Model

The problem of consistent estimation of the slope parameter in an ultrastructural model with replicated observations is considered in this article. A consistent estimator based on a weighted arithmetic mean of two inconsistent least squares estimators is proposed which is independent of any unknown quantity. The efficiency properties of this estimator are studied.     

Computer-Generated Change-Over Designs for Correlated Observations

Change-over designs with independently distributed errors in the model have been studied extensively in the literature. Martin and Eccleston (2001 Martin , R. J. , Eccleston , J. A. ( 2001 ). Optimal and near optimal designs for dependent observations . Statist. Applic. 3 : 101 – 116 . [Google Scholar]) gave an algorithm for the generation of efficient change-over designs when the errors are correlated. This article proposes an algorithm for the generation of efficient change-over designs for estimation of direct effects of treatments in the presence of first-order residual effects in the model and when the errors are correlated.     

An Investigation of Quantile Function Estimators Relative to Quantile Confidence Interval Coverage

In this article, we investigate the limitations of traditional quantile function estimators and introduce a new class of quantile function estimators, namely, the semi-parametric tail-extrapolated quantile estimators, which has excellent performance for estimating the extreme tails with finite sample sizes. The smoothed bootstrap and direct density estimation via the characteristic function methods are developed for the estimation of confidence intervals. Through a comprehensive simulation study to compare the confidence interval estimations of various quantile estimators, we discuss the preferred quantile estimator in conjunction with the confidence interval estimation method to use under different circumstances. Data examples are given to illustrate the superiority of the semi-parametric tail-extrapolated quantile estimators. The new class of quantile estimators is obtained by slight modification of traditional quantile estimators, and therefore, should be specifically appealing to researchers in estimating the extreme tails.     

Vector random fields with compactly supported covariance matrix functions

The objective of this paper is to construct covariance matrix functions whose entries are compactly supported, and to use them as building blocks to formulate other covariance matrix functions for second-order vector stochastic processes or random fields. In terms of the scale mixture of compactly supported covariance matrix functions, we derive a class of second-order vector stochastic processes on the real line whose direct and cross covariance functions are of Pólya type. Then some second-order vector random fields in R^d${\mathbb{R}}^d$ whose direct and cross covariance functions are compactly supported are constructed by using a convolution approach and a mixture approach.     

Fitting of self-exciting threshold autoregressive moving average nonlinear time-series model through genetic algorithm and development of out-of-sample forecasts

Self-exciting threshold autoregressive moving average (SETARMA) nonlinear time-series model is considered here. Sufficient conditions for invertibility and stationarity are derived. Parameter estimation algorithm is developed by employing real-coded genetic algorithm stochastic optimization procedure. A significant feature of the work done is that optimal out-of-sample forecasts up to three-step ahead and their forecast error variances are derived analytically. Relevant computer programs are written in statistical analysis system (SAS) and C. As an illustration, annual mackerel catch time-series data are considered. Forecast performance of the fitted model for hold-out data is evaluated by using Naive and Monte Carlo approaches. It is found that optimal out-of-sample forecast values are quite close to actual values and estimated variances are quite close to theoretical values. Superiority of the SETARMA model over the SETAR model for equal predictive ability through Diebold–Mariano test is also established.     

Non-nested model selection based on the quantiles and it’s application in time series

We consider the problem of model selection based on quantile analysis and with unknown parameters estimated using quantile leasts squares. We propose a model selection test for the null hypothesis that the competing models are equivalent against the alternative hypothesis that one model is closer to the true model. We follow with two applications of the proposed model selection test. The first application is in model selection for time series with non-normal innovations. The second application is in model selection in the NoVas method, short for normalizing and variance stabilizing transformation, forecast. A set of simulation results also lends strong support to the results presented in the paper.