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51.
The purpose of the article is, in case of one sample, to obtain tests concerning the parameter in the power series distribution in one parameter using Ku11back-Leibier information measure. The class of power series distibutions contains a host of discrete distributions. Ve illustrate the general results obtained in case of the geometric distibution.  相似文献   
52.
In this paper, functional coefficient autoregressive (FAR) models proposed by Chen and Tsay (1993) are considered. We propose a diagnostic statistic for FAR models constructed by comparing between parametric and nonparametric estimators of the functional form of the FAR models. We show asymptotic properties of our statistic mathematically and it can be applied to the estimation of the delay parameter and the specification of the functional form of FAR models.  相似文献   
53.
比较了不同的几种岭参数选择方法的应用效果,结果表明,几种方法中没有一种方法被认为是优于其它的方法。但在均方误差准则下.几种岭参数选择方法所获得的估计都改进了设计阵呈病态时的最小二乘估计。  相似文献   
54.
This paper provides a novel mechanism for identifying and estimating latent group structures in panel data using penalized techniques. We consider both linear and nonlinear models where the regression coefficients are heterogeneous across groups but homogeneous within a group and the group membership is unknown. Two approaches are considered—penalized profile likelihood (PPL) estimation for the general nonlinear models without endogenous regressors, and penalized GMM (PGMM) estimation for linear models with endogeneity. In both cases, we develop a new variant of Lasso called classifier‐Lasso (C‐Lasso) that serves to shrink individual coefficients to the unknown group‐specific coefficients. C‐Lasso achieves simultaneous classification and consistent estimation in a single step and the classification exhibits the desirable property of uniform consistency. For PPL estimation, C‐Lasso also achieves the oracle property so that group‐specific parameter estimators are asymptotically equivalent to infeasible estimators that use individual group identity information. For PGMM estimation, the oracle property of C‐Lasso is preserved in some special cases. Simulations demonstrate good finite‐sample performance of the approach in both classification and estimation. Empirical applications to both linear and nonlinear models are presented.  相似文献   
55.
具有多个出口的自动化立体仓库系统是一种将存储和分拣相结合的新型仓储技术,其最典型的特征是在货架底层有很多个出库位置以供取货人员分拣。研究此系统中出入库任务排序与出口选择的集成优化问题,以最小化堆垛机完成所有任务的移动距离为目标,将此问题转化为一个混合整数规划模型。根据问题的特点设计了两阶段启发式算法求解此问题,数值结果表明设计的算法能在较短时间内给出近似最优解,同时与企业常用的先到先服务方法相比,该算法可以缩短超过20%的移动距离。  相似文献   
56.
资产专用性对确权后农地流转的影响   总被引:1,自引:0,他引:1  
农地确权后,农户对农地转出多持中立或否定的态度,这与产权明晰促进交易的产权理论大相径庭。文章探讨了资产专用性对确权后农地流转的作用机理,并运用吉林省9市1444个农户数据对其进行实证分析。结果表明:农地确权后,土地资产、农业资产、地理位置以及人力资本等专用性抑制农户转出农地,农业资产和人力资本专用性抑制农户提高农地租金,而社会资本专用性则分别存在促进作用;农业资产、地理位置以及人力资本等专用性抑制农户更长时间转出农地;农业资产专用性对转出农地须要签订合约具有抑制作用,而地理位置专用性则存在促进作用。  相似文献   
57.
The binary logistic regression is a widely used statistical method when the dependent variable has two categories. In most of the situations of logistic regression, independent variables are collinear which is called the multicollinearity problem. It is known that multicollinearity affects the variance of maximum likelihood estimator (MLE) negatively. Therefore, this article introduces new shrinkage parameters for the Liu-type estimators in the Liu (2003) in the logistic regression model defined by Huang (2012) in order to decrease the variance and overcome the problem of multicollinearity. A Monte Carlo study is designed to show the goodness of the proposed estimators over MLE in the sense of mean squared error (MSE) and mean absolute error (MAE). Moreover, a real data case is given to demonstrate the advantages of the new shrinkage parameters.  相似文献   
58.
史书记载的 “鲜卑山”共有五处,通过对比分析可以发现,这五处“鲜卑山”实际上指的是三座山,即鲜卑的发源地、位于大兴安岭南段的“大鲜卑山”,朝阳附近、混有乌桓、匈奴部落的慕容鲜卑部落联盟聚居地“鲜卑山”和敦煌附近、以鲜卑为主体,包含乌桓、匈奴及氐、羌部落的吐谷浑部落联盟聚居地“鲜卑山”,这三座山不仅是鲜卑族兴起和发展阶段的展示,更是鲜卑诸政权的摇篮,对我国古代历史的走向有着重大影响。  相似文献   
59.
We propose an exploratory data analysis approach when data are observed as intervals in a nonparametric regression setting. The interval-valued data contain richer information than single-valued data in the sense that they provide both center and range information of the underlying structure. Conventionally, these two attributes have been studied separately as traditional tools can be readily used for single-valued data analysis. We propose a unified data analysis tool that attempts to capture the relationship between response and covariate by simultaneously accounting for variability present in the data. It utilizes a kernel smoothing approach, which is conducted in scale-space so that it considers a wide range of smoothing parameters rather than selecting an optimal value. It also visually summarizes the significance of trends in the data as a color map across multiple locations and scales. We demonstrate its effectiveness as an exploratory data analysis tool for interval-valued data using simulated and real examples.  相似文献   
60.
A smoothed bootstrap method is presented for the purpose of bandwidth selection in nonparametric hazard rate estimation for iid data. In this context, two new bootstrap bandwidth selectors are established based on the exact expression of the bootstrap version of the mean integrated squared error of some approximations of the kernel hazard rate estimator. This is very useful since Monte Carlo approximation is no longer needed for the implementation of the two bootstrap selectors. A simulation study is carried out in order to show the empirical performance of the new bootstrap bandwidths and to compare them with other existing selectors. The methods are illustrated by applying them to a diabetes data set.  相似文献   
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