A MODIFICATION OF THE SEQUENTIAL PROBABILITY RATIO TEST FOR TESTING A NORMAL MEAN

A modification of the sequential probability ratio test is proposed in which Wald's parallel boundaries are broken at some preassigned point of the sample number axis and Anderson's converging boundaries are used prior to that. Read's partial sequential probability ratio test can be considered as a special case of the proposed procedure. As far as 'the maximum average sample number reducing property is concerned, the procedure is as good as Anderson's modified sequential probability ratio test.     

A cusum test in the linear regression model with serially correlated disturbances

This paper considers a modified CUSUM test, suggested by Dufour (1982) for parameter instability and structural change with an unknown change point in a linear model with serially correlated disturbances, in which a preliminary estimate of the autoregressive coefficient for the error process is obtained, and used to transform the data. Then the standard CUSUM statistic is calculated on the transformed data. This paper derives the asymptotic distribution of the modified CUSUM test. We show that the modified CUSUM test retains its asymptotic significance level, i.e., the modified CUSUM test has the same asymptotic distribution as the CUSUM test with serially uncorrelated errors.     

Robust Confidence Regions for Incomplete Models

Call an economic model incomplete if it does not generate a probabilistic prediction even given knowledge of all parameter values. We propose a method of inference about unknown parameters for such models that is robust to heterogeneity and dependence of unknown form. The key is a Central Limit Theorem for belief functions; robust confidence regions are then constructed in a fashion paralleling the classical approach. Monte Carlo simulations support tractability of the method and demonstrate its enhanced robustness relative to existing methods.     

Testing homogeneity of difference of two proportions for stratified correlated paired binary data

In ophthalmologic or otolaryngologic study, each subject may contribute paired organs measurements to the analysis. A number of statistical methods have been proposed on bilateral correlated data. In practice, it is important to detect confounding effect by treatment interaction, since ignoring confounding effect may lead to unreliable conclusion. Therefore, stratified data analysis can be considered to adjust the effect of confounder on statistical inference. In this article, we investigate and derive three test procedures for testing homogeneity of difference of two proportions for stratified correlated paired binary data in the basis of equal correlation model assumption. The performance of proposed test procedures is examined through Monte Carlo simulation. The simulation results show that the Score test is usually robust on type I error control with high power, and therefore is recommended among the three methods. One example from otolaryngologic study is given to illustrate the three test procedures.     

制定反倾销策略的一种决策方法研究

研究倾销幅度变化引致的进口国经济和就业的变化对进口国制定反倾销策略有重要参考价值。本文建立了计算倾销对进口国经济直接、关联和完全影响的可计算局部均衡-投入占用产出模型。在该模型的基础上,逐一分析倾销幅度的变化所引起的进口国产业总产出的变化、就业的变化和消费者福利的变化,并给出了它们之间变化关系的经济数学表达式。该研究为制定反倾销策略提供了一种决策方法。     

基于联立方程模型的公司治理溢价研究——兼谈如何检验公司治理评价指标的有效性

公司治理溢价研究可以揭示公司治理与企业价值之间的互动机理,不仅有助于深化和丰富公司治理理论,为上市公司优化公司治理指明方向和重点,而且有助于投资者全面评估企业价值.而对公司治理的客观评价是公司治理溢价研究中的关键问题,本文在以往研究成果基础上,以上证公司治理板块的评选结果为参照样本,给出了检验公司治理评价指标有效性的科学方法,进而验证了以DEA方法构建的公司治理效率值指标的有效性;在此基础上利用联立方程模型对公司治理溢价进行研究,解决了公司治理与企业价值之间可能存在的内生性问题;以2007年中国沪市578家A股公司为样本对联立方程模型进行估计.结果表明,中国股票市场存在公司治理溢价,公司治理效率值每增加0.1,流通盘市场附加值就会有37.2%的溢价.