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851.
Ryszard Zieliński 《Statistics》2013,47(4):453-462
According to Pitman's Measure of Closeness, if T1and T2are two estimators of a real parameter $[d], then T1is better than T2if Po[d]{\T1-o[d] < \T2-0[d]\} > 1/2 for all 0[d]. It may however happen that while T1is better than T2and T2is better than T3, T3is better than T1. Given q ? (0,1) and a sample X1, X2, ..., Xnfrom an unknown F ? F, an estimator T* = T*(X1,X2...Xn)of the q-th quantile of the distribution F is constructed such that PF{\F(T*)-q\ <[d] \F(T)-q\} >[d] 1/2 for all F?F and for all T€T, where F is a nonparametric family of distributions and T is a class of estimators. It is shown that T* =Xj:n'for a suitably chosen jth order statistic. 相似文献
852.
Ancop Chaturvedi 《统计学通讯:理论与方法》2013,42(8):2275-2284
The present paper considers a family of ordinary ridge regression estimators in the linear regression model when the disturbances covariance matrix depends upon a few unknown parameters. An asymptotic expansion for the distribution of the ridge regression estimator is developed and under the quadratic loss function its asymptotic risk is compared with that of the feasible GLS estimator. 相似文献
853.
This note presents an extension of Q-method of analysis for binary designs given by Rao (1956) to n-ary balanced and partially balanced block designs. Here a linked n-ary block (LNB) design is defined as the dual of balanced n-ary (BN) design. Having a note on Yates’ (1939, 1940) method of P-analysis, we further extend the expressions for binary linked block (LB) designs given by Rao (1956) to linked n-ary block (LNB) designs which admit easy estimation of parameters for these type of all n-ary designs. 相似文献
854.
Procurement lead time estimates are critical factors in production planning; however, they are generally based on a buyer&apos;s experience. The Westinghouse Corporation developed a linear model which successfully predicted procurement lead times for hot and cold rolled steel. This paper discusses nine models which use utilization and inventory data to predict lead time planning factors for aluminum, magnesium, steel and titanium products. The Lockheed-Georgia Company, which produces aerospace products, provided data for this research. The functional form of the models is significant and suggests that a nonlinear transformation of utilization based upon simple queueing models is a significant predictor of lead time duration. 相似文献
855.
张海媚 《西南交通大学学报(社会科学版)》2012,(2):78-84
在表"使令"义上,唐代以前,主要以"使"、"令"为主;宋金时期,"教(交)"取代"使"和"令"成为当时口语中表"使令"义的主导词;而大约在明末清初,"教"在与"叫"的竞争中失去优势,被淘汰出局,"叫"成为至今表"使令"义的主导词。"教"本读去声,表"使令"义的"教"读作平声是为与原义区别而产生的一种破读,之所以后来又重新读为去声,是受"叫"读音影响的结果。 相似文献
856.
AbstractIn this article, in the framework of sublinear expectation initiated by Peng, we derive a strong law of large numbers (SLLN) for negatively dependent and non identical distributed random variables. This result includes and extends some existing results. Furthermore, we give two examples of our result for applications. 相似文献
857.
In sequencing problems for mixed-model assembly line in JIT production system, the Goal Chasing method (GC) is widely used for parts used leveling goal. The difference in assembly time of each product is not taken into consideration in the Goal Chasing method. Assembly time usually varies with product types. In recent years, the Time-Based Goal Chasing method (TBGC) has been proposed. The advantage of TBGC is to consider the influence of different assembly time of each product and idle time in production period. TBGC, however, has been only applied to single work station problems. In this paper, TBGC is applied to an assembly line problem with multiple work stations. Furthermore, the sequencing method and use of Simulated Annealing (SA) or Local Search (LS) for this problem are proposed. 相似文献
858.
Two often-quoted necessary and sufficient conditions for ordinary least squares estimators to be best linear unbiased estimators are described. Another necessary and sufficient condition is described, providing an additional tool for checking to see whether the covariance matrix of a given linear model is such that the ordinary least squares estimator is also the best linear unbiased estimator. The new condition is used to show that one of the two published conditions is only a sufficient condition. 相似文献
859.
Julio L. Peixoto 《The American statistician》2013,67(4):311-313
Significance tests on coefficients of lower-order terms in polynomial regression models are affected by linear transformations. For this reason, a polynomial regression model that excludes hierarchically inferior predictors (i.e., lower-order terms) is considered to be not well formulated. Existing variable-selection algorithms do not take into account the hierarchy of predictors and often select as “best” a model that is not hierarchically well formulated. This article proposes a theory of the hierarchical ordering of the predictors of an arbitrary polynomial regression model in m variables, where m is any arbitrary positive integer. Ways of modifying existing algorithms to restrict their search to well-formulated models are suggested. An algorithm that generates all possible well-formulated models is presented. 相似文献
860.
Geneviève Lessard Catherine Flynn Pierre Turcotte Dominique Damant Jean‐François Vézina Marie‐France Godin France Paradis Rhea Delisle Yennelys Alcedo Lorraine Juneau Linda Rock Simon Rondeau‐Cantin 《Child & Family Social Work》2010,15(4):492-500
The situation of families undergoing separation in a context of co‐occurrence of intimate partner violence (IPV) and child maltreatment raises certain issues related to child custody. The results presented in this paper were collected and analysed within the framework of a qualitative study aiming to identify the principal points of agreement and the main controversies amongst practitioners in several different types of organizations. Focus groups were held with a total of 43 practitioners from six different settings concerned with child custody in cases of co‐occurrence of IPV and child maltreatment. Although they agreed on the importance of ensuring the safety of victims of violence, their views diverged on three points: (1) the importance of preserving the father–child relationship; (2) collaboration between voluntary organizations and semi‐voluntary or legal agencies; and (3) consideration of cultural differences. 相似文献