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991.
This paper employs some variants of the usual Kronecker product to construct orthogonal factorial designs controlling the interaction efficiencies. The methods suggested have a fairly wide coverage and the resulting designs involve a small number of replicates.  相似文献   
992.
Theorerms are proved for the maxima and minima of IIRi!/IICj!/T!IIyij ! over r× c contingcncy tables Y=(yij) with row sums R1,…,Rr, column sums C1,…,Cc, and grand total T. These results are imlplemented into the network algorithm of Mehta and Patel (1983) for computing the P-value of Fisher's exact test for unordered r×c contingency tables. The decrease in the amount of computing time can be substantial when the column sums are very different.  相似文献   
993.
In this paper we consider the Neyman accuracy and the Wolfowitz accuracy of the Stein type improved confidence interval I?S for the disturbance variance in a linear regression model. The Neyman accuracy is a measure related to the unbiasedness of a confidence interval, and the Wolfowitz accuracy is related to the closeness of the endpoints to the true parameter. We show that I?S is not unbiased and give some numerical results for the Neyman accuracy. As for the Wolfowitz accuracy we derive the sufficient condition for I?S to improve on the usual confidence interval under this criterion and show numerically that a large degree of improvement can be obtainted.  相似文献   
994.
The objectives of this article are threefold—(1) to test target-zone models using more efficient and direct econometric methodology than previous research, (2) to identify an implicit band, if it exists, from observed data and to test target-zone models based on the estimated implicit band rather than the stated official band, and (3) to examine whether the exchange rate can be modeled as a managed float system with a central parity that lacks a band. We find strong evidence that a model with intramarginal intervention and a narrower implicit (unofficial) band can describe the dynamics of the French franc/Deutsche mark exchange rate from January 1, 1987–July 30, 1993.  相似文献   
995.
根据矮塔斜拉桥的受力特点,介绍了梁体关键受力部位测点的布置方案。通过对实测应力值同设计理论值进行的对比分析,研究了该桥施工过程中的主梁受力规律。同时对该桥主梁应力横向分布规律和日照温差对主梁应力的影响规律进行了研究分析。  相似文献   
996.
随着创业能力学习论逐渐被大家接受,创业者的创业能力如何训练提高和评价成为人们关注的焦点.通过资料综述确定成功创业者拥有的创业能力特征因子,即动机、品质、自我认知、价值观和深层次创业知识经验与技能,根据5种因子特征,在E-prime测评软件平台上分别采用内隐联想测试(IAT)、镶嵌图形测试和斯特鲁普效应测试(Stroop),可以建立一种创业能力情景模拟综合测评方法,设计其测评系统程序.两组被试测评结果相关分析表明:创业动机不同的两组被试IAT测评分在置信度95%区间存在显著差异;创业能力不同的两组被试总测评分也存在显著差异.  相似文献   
997.
This paper considers Lagrange Multiplier (LM) and Likelihood Ratio (LR) tests for determining the cointegrating rank of a vector autoregressive system. n order to deal with outliers and possible fat-tailedness of the error process, non-Gaussian likelihoods are used to carry out the estimation. The limiting distributions of the tests based on these non-Gaussian pseudo-)likelihoods are derived. These distributions depend on nuisance parameters. An operational procedure is proposed to perform inference. It appears that the tests based on non-Gaussian pseudo-likelihoods are much more powerful than their Gaussian counterparts if the errors are fat-tailed. Moreover, the operational LM-type test has a better overall performance than the LR-type test. Copyright O 1998 by Marcel Dekker, Inc.  相似文献   
998.
This article presents the results of a simulation study investigating the performance of an approach developed by Miller and Landis (1991) for the analysis of clustered categorical responses. Evaluation of this “two-step” approach, which utilizes the method of moments to estimate the extra-variation pardmeters and subsequently incorporates these parameters into estimating equations for modelling the marginal expectations, is carried out in an experimental setting involving a comparison between two groups of observations. We assume that data for both groups are collected from each cluster and responses are measured on a three-point ordinal scale. The performance of the estimators used in both “steps” of the analysisis investigated and comparisons are made to an alternative analysismethod that ignores the clustering. The results indicate that in the chosen setting the test for a difference between groups generally operatbs at the nominal α=0.05 for 10 or more clusters and hasincreasing power with both an increasing number of clusters and an inrreasing treatment effect. These results provide a striking contrasc to those obtained from an improper analysis that ignores clustering.  相似文献   
999.
In modelling a system structure it is often important to test the constancy of the structural parameters. If the hypothesis of constant parameters is rejected we wish to characterize the parameter variation. In this paper we examine the usefulness of the MOSUMSQ test statistics for locating and characterizing the parameter variation in linear regression models. The means and the variances of the test statistics are given for non-random parameter variation. The observed path of the MOSUMSQ test statistics provides valuable knowledge about the time of the onset of the parameter change and whether it is instantaneous or gradual.  相似文献   
1000.
The score function is associated with some optimality features in statistical inference. This review article looks on the central role of the score in testing and estimation. The maximization of the power in testing and the quest for efficiency in estimation lead to score as a guiding principle. In hypothesis testing, the locally most powerful test statistic is the score test or a transformation of it. In estimation, the optimal estimating function is the score. The same link can be made in the case of nuisance parameters: the optimal test function should have maximum correlation with the score of the parameter of primary interest. We complement this result by showing that the same criterion should be satisfied in the estimation problem as well.  相似文献   
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