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441.
德语、波兰语等语言wh成分部分移位问句发生wh特征移位,其带有i[Q]和u[wh]*特征的标句中心词C与带有i[wh]和u[Q]特征的wh成分进行多重一致关系特征核查使后者处于低于句首辖域位置的Spec-CP位置.匈牙利语、阿尔巴尼亚语等语言wh成分部分移位问句进行焦点特征移位,其带有i[Q]和u[Fbc]*特征的焦点中心词F与带有i[Foc]和u[Q]特征的wh成分进行Foc特征一致关系核查并使后者前移置于CP之后的Spec-FP位置.  相似文献   
442.
A counter-example shows that the proof of optimality of the marginal likelihood estimating function for parameter of interest, under the conditions assumed in Lloyd (1987), contains a gap and is, thus, invalid. The same comment applies to the generalized version of Lloyd’s Theorem given by Bhapkar and Srinivasan (1993). In the light of known results concerning Fisher information for parameter of interest and partial sufficiency of a suitable statistic, the counter-example reveals a similar gap in the proof of corollary 3.2 of Bhapkar (1991).  相似文献   
443.
A multiproduct translog cost function is estimated and used to calculate elasticities of factor substitution in the production of police services. The data come from Florida's municipal police departments and are for 1982–1983. It is found that substitution elasticities between any pair of inputs in police production are significantly different from unity. This result is inconsistent with the Cobb–Douglas production function—a functional form that has been extensively employed in empirical studies of police production.  相似文献   
444.
The modelling and analysis of count-data time series are areas of emerging interest with various applications in practice. We consider the particular case of the binomial AR(1) model, which is well suited for describing binomial counts with a first-order autoregressive serial dependence structure. We derive explicit expressions for the joint (central) moments and cumulants up to order 4. Then, we apply these results for expressing moments and asymptotic distribution of the squared difference estimator as an alternative to the sample autocovariance. We also analyse the asymptotic distribution of the conditional least-squares estimators of the parameters of the binomial AR(1) model. The finite-sample performance of these estimators is investigated in a simulation study, and we apply them to real data about computerized workstations.  相似文献   
445.
对信息不完全条件下的应急物资转运系统建立了一个随机Petri网模型。根据这一模型,找到了计算各个状态中驻留时间、卡车的平均利用率、物资分发点等待物资的平均等待概率、物资分发点等待物资的平均等待时间的方法。使用这个模型对某企业在汶川特大地震应急物资保障中的物资转运系统的性能进行了计算,性能计算的主要结果与实际统计数据吻合。  相似文献   
446.
A bandwidth selection method that combines the concept of least-squares cross-validation and the plug-in approach is being introduced in connection with kernel density estimation. A simulation study reveals that this hybrid methodology outperforms some commonly used bandwidth selection rules. It is shown that the proposed approach can also be readily employed in the context of variable kernel density estimation. We conclude with two illustrative examples.  相似文献   
447.
Three nonparametric methods for estimating a change-point, and the mean function Pefore and after the change has occurred are developed for a restricted class of processes. The estimators which are developed are intuitive, and their asymptotic behavior is studied, Konte Cario cornparisoris are undertaKen for smali and moderate samples.  相似文献   
448.
The L statistic is extended to allow incomplete or partial rankings within groups. As a special case of these extensions, tests for ofered alternatives analogous to the page test are provided for other than complete rankings. A two group illustration is provided by an alternative analysis of the Bradley and Terry taste-testing experiment on pork-roasts.  相似文献   
449.
Molecular markers combined with powerful statistical tools have made it possible to detect and analyze multiple loci on the genome that are responsible for the phenotypic variation in quantitative traits. The objectives of the study presented in this paper are to identify a subset of single nucleotide polymorphism (SNP) markers that are associated with a particular trait and to construct a model that can best predict the value of the trait given the genotypic information of the SNPs using a three-step strategy. In the first step, a genome-wide association test is performed to screen SNPs that are associated with the quantitative trait of interest. SNPs with p-values of less than 5% are then analyzed in the second step. In the second step, a large number of randomly selected models, each consisting of a fixed number of randomly selected SNPs, are analyzed using the least angle regression method. This step will further remove redundant SNPs due to the complicated association among SNPs. A subset of SNPs that are shown to have a significant effect on the response trait more often than by chance are considered for the third step. In the third step, two alternative methods are considered: the least angle shrinkage and selection operation and sparse partial least squares regression. For both methods, the predictive ability of the fitted model is evaluated by an independent test set. The performance of the proposed method is illustrated by the analysis of a real data set on Canadian Holstein cattle.  相似文献   
450.
A simple to use, straight coded, Fortran 4 algorithm, is presented. This algorithm has the ability to:

1) evaluate the Incomplete Gamma function, Y(r,λx), for parameter values in the range 0 < r < 20.0 and upper limit of integration values in the range 0 75.0;

2) evaluate both the first and second partial derivatives of y with respect to the parameter

3) evaluate both the Euler Di and Trigamma functions, ψ(r) and if ψ′(r)for 0<rf.20.0.

In all cases the accuracy is nine or more significant figures. The user has several choices of data output format  相似文献   
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