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11.
This study investigates the extent to which formal governance mechanisms such as contracts and equity ownership affect interfirm coordination and partnership performance. We analysed data from a survey of 301 Korean firms to show that interfirm coordination partially mediates the relationship between contract completeness, defined as the extent to which a contract specifies task operations and contingencies, and partnership performance. Furthermore, we find that more complete contracts can attenuate the negative effects of equity ownership on coordination, and that this effect is particularly strong when partner tasks are interdependent and relational norms are weak.  相似文献   
12.
In this article, we propose a new class of semiparametric instrumental variable models with partially varying coefficients, in which the structural function has a partially linear form and the impact of endogenous structural variables can vary over different levels of some exogenous variables. We propose a three-step estimation procedure to estimate both functional and constant coefficients. The consistency and asymptotic normality of these proposed estimators are established. Moreover, a generalized F-test is developed to test whether the functional coefficients are of particular parametric forms with some underlying economic intuitions, and furthermore, the limiting distribution of the proposed generalized F-test statistic under the null hypothesis is established. Finally, we illustrate the finite sample performance of our approach with simulations and two real data examples in economics.  相似文献   
13.
介绍了对电站发动机组凝汽器进行状态监测和故障诊断的技术诊断自动化系统的研究和实现,实践证明,开发的系统对改善凝汽器性能、提高电站整体性能具有重要意义。  相似文献   
14.
基于快速以太局网中分布式并行服务器通信特点和对网络协议栈的分析,设计并实现了一种分布式操作系统传输协议。该协议在维持通用编程接口的同时,精简网络协议栈底层的冗余操作,减少操作系统干预和协议自维护开销。在8个节点的服务器系统上的测试结果表明,分布式操作系统传输协议获得比用户数据报协议更小的往返延迟和系统开销,应用环境下有约20%的增益,能有力地支持系统扩展和大并发访问服务。  相似文献   
15.
笔者系统总结了我国城乡差距、城乡关系失调的具体表现,并进一步分析了城乡发展差距过大对国民经济和社会发展的影响以及统筹城乡发展的现实意义,继而从改革城乡分治的管理体制,加快城镇化进程,推动城乡联动的工业化路线等方面提出了统筹城乡发展的对策建议。  相似文献   
16.
Generalized method of moments (GMM) is used to develop tests for discriminating discrete distributions among the two-parameter family of Katz distributions. Relationships involving moments are exploited to obtain identifying and over-identifying restrictions. The asymptotic relative efficiencies of tests based on GMM are analyzed using the local power approach and the approximate Bahadur efficiency. The paper also gives results of Monte Carlo experiments designed to check the validity of the theoretical findings and to shed light on the small sample properties of the proposed tests. Extensions of the results to compound Poisson alternative hypotheses are discussed.  相似文献   
17.
A test of congruence among distance matrices is described. It tests the hypothesis that several matrices, containing different types of variables about the same objects, are congruent with one another, so they can be used jointly in statistical analysis. Raw data tables are turned into similarity or distance matrices prior to testing; they can then be compared to data that naturally come in the form of distance matrices. The proposed test can be seen as a generalization of the Mantel test of matrix correspondence to any number of distance matrices. This paper shows that the new test has the correct rate of Type I error and good power. Power increases as the number of objects and the number of congruent data matrices increase; power is higher when the total number of matrices in the study is smaller. To illustrate the method, the proposed test is used to test the hypothesis that matrices representing different types of organoleptic variables (colour, nose, body, palate and finish) in single‐malt Scotch whiskies are congruent.  相似文献   
18.
Alternative boundaries for CUSUM tests   总被引:1,自引:0,他引:1  
Zeileis  Achim 《Statistical Papers》2004,45(1):123-131
Alternative boundaries for the common Recursive (or Standard) CUSUM test and the OLS-based CUSUM test for structural change are suggested and their properties are examined by simulation of expectedp values. The poor power of the tests for early and late structural changes can be improved for the OLS-based version, whereas this weakness of the Recursive CUSUM test cannot be overcome by the new boundaries. Research supported by the Austrian Science Foundation (FWF) under grant SFB#010 (‘Adaptive Information Systems and Modeling in Economics and Management Science’).  相似文献   
19.
Many applications of nonparametric tests based on curve estimation involve selecting a smoothing parameter. The author proposes an adaptive test that combines several generalized likelihood ratio tests in order to get power performance nearly equal to whichever of the component tests is best. She derives the asymptotic joint distribution of the component tests and that of the proposed test under the null hypothesis. She also develops a simple method of selecting the smoothing parameters for the proposed test and presents two approximate methods for obtaining its P‐value. Finally, she evaluates the proposed test through simulations and illustrates its application to a set of real data.  相似文献   
20.
The robustness of Mauchly's sphericity test criterion when sampling from a mixture of two multivariate normal distributions is studied. The distribution of the sphericity test criterion when the sample covariance matrix has a non-central Wishart density of rank one is derived in terms of Meijer's G-functions; its distribution under the mixture model is then deduced. The robustness is studied by computing actual significance levels of the test under the mixture model using the critical values under the usual normal model.  相似文献   
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