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581.
本文给出由等差数列产生的两类级数的n项部分和公式,证明了其中一类级数的收敛性,并给出求和公式.  相似文献   
582.
Holler  Manfred J.  Ono  Rie  Steffen  Frank 《Theory and Decision》2001,50(4):383-395
In this paper we will discuss constraints on the number of (non-dummy) players and on the distribution of votes such that local monotonicity is satisfied for the Public Good Index. These results are compared to properties which are related to constraints on the redistribution of votes (such as implied by global monotonicity). The discussion shows that monotonicity is not a straightforward criterion of classification for power measures. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
583.
College English Test is an important national test for Chinese college students, this paper introduces the distribution of scores, time of examination, and analyses the four parts in CET ,such as listening comprehension, reading comprehension, integrated testing, and writing based on testing theories.  相似文献   
584.

Suppose that an order restriction is imposed among several p-variate normal mean vectors. We are interested in the problems of estimating these mean vectors and testing their homogeneity under this restriction. These problems are multivariate extensions of Bartholomew's (1959) ones. For the bivariate case, these problems have been studied by Sasabuchi et al. (1983) and (1998) and some others. In the present paper we examine the convergence of an iterative algorithm for computing the maximum likelihood estimator when p is larger than two. We also study some test procedures for testing homogeneity when p is larger than two.  相似文献   
585.
586.
Abstract

We propose a simple procedure based on an existing “debiased” l1-regularized method for inference of the average partial effects (APEs) in approximately sparse probit and fractional probit models with panel data, where the number of time periods is fixed and small relative to the number of cross-sectional observations. Our method is computationally simple and does not suffer from the incidental parameters problems that come from attempting to estimate as a parameter the unobserved heterogeneity for each cross-sectional unit. Furthermore, it is robust to arbitrary serial dependence in underlying idiosyncratic errors. Our theoretical results illustrate that inference concerning APEs is more challenging than inference about fixed and low-dimensional parameters, as the former concerns deriving the asymptotic normality for sample averages of linear functions of a potentially large set of components in our estimator when a series approximation for the conditional mean of the unobserved heterogeneity is considered. Insights on the applicability and implications of other existing Lasso-based inference procedures for our problem are provided. We apply the debiasing method to estimate the effects of spending on test pass rates. Our results show that spending has a positive and statistically significant average partial effect; moreover, the effect is comparable to found using standard parametric methods.  相似文献   
587.
本文采用短波近红外漫反射光谱法对氨苄西林粉末药品中主要成分氨苄西林进行快速、无损非破坏快速定量分析。采用偏最小二乘法(PLS)建立近红外光谱信息与待测组分含量间的最佳数学校正模型。讨论了光谱的预处理方法和主成分数对PLS定量预测能力的影响,并对预测集样品含量进行预测,得到了较为满意的结果。  相似文献   
588.
This paper studies the special case of the triangular system of equations in Vytlacil and Yildiz (2007), where both dependent variables are binary but without imposing the restrictive support condition required by Vytlacil and Yildiz (2007) for identification of the average structural function (ASF) and the average treatment effect (ATE). Under weak regularity conditions, we derive upper and lower bounds on the ASF and the ATE. We show further that the bounds on the ASF and ATE are sharp under some further regularity conditions and an additional restriction on the support of the covariates and the instrument.  相似文献   
589.
Recent research in information systems and operations management has considered the positive impacts of information technology (IT). However, an undesirable side effect of firms’ increasing reliance on IT to support the distribution and delivery of goods and services to customers is a greater exposure to a diverse set of IT security risks. One such risk is intentional employee misuse of technology resources. In this article, we draw upon modern deterrence frameworks to develop a predictive model of technology misuse intention that incorporates formal and informal sanctions as well as employment context factors. The model specifies previously untested relationships between formal and informal sanctions, thereby providing fresh insight into the role of sanctions in deterring technology misuse in organizations. Our results suggest that a predisposition toward the need for social approval and moral beliefs regarding the behavior are key determinants of technology misuse. Contrary to criminological research that has questioned the relative importance of formal sanctions in the deterrence process, we also found that the threat of formal sanctions has both direct and indirect influences on technology misuse intention. Further, from an employment context standpoint, employees who spend more working days away from the office (i.e., “virtual” mode) appear more inclined to misuse their organization's technology resources. The findings have implications for the research and practice of technology management.  相似文献   
590.
FDI对我国经济增长的影响分析及检验   总被引:2,自引:1,他引:1  
改革开放以来,我国经济得到迅速发展。外商直接投资(Foreign Direct Investment,以下简称FDI)的引入规模逐渐扩大,成为我国投资资金的重要来源之一。随着改革的不断深入,实际使用的FDI对我国经济发展的影响也在发生着变化。为研究FDI对我国经济增长的实际影响,结合FDI对东道国经济影响研究的相关文献,通过协整检验、Granger因果检验和误差修正模型,对我国1983—2010年间实际使用FDI与我国经济增长之间的长期和短期关系分别进行实证分析。结果表明,无论从长期还是短期来看,实际使用FDI对我国经济增长都有一定的正向促进作用。  相似文献   
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