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91.
Based on the insightful work of Olsen (1980 Olsen , R. J. ( 1980 ). A least squares correction for selectivity bias . Econometrica 48 : 18151820 .[Crossref], [Web of Science ®] [Google Scholar]) for the linear context, a generic and unifying framework is developed that affords a simple extension of the classical method of Heckman (1974 Heckman , J. ( 1974 ). Shadow prices, market wages, and labor supply . Econometrica 42 : 679694 .[Crossref], [Web of Science ®] [Google Scholar], 1976 Heckman , J. ( 1976 ). The common structure of statistical models of truncation sample selection and limited dependent variables and a simple estimator for such models . Annals of Economic and Social Measurement 5 : 475492 . [Google Scholar], 1978 Heckman , J. ( 1978 ). Dummy endogenous variables in a simultaneous equation system . Econometrica 46 : 931959 .[Crossref], [Web of Science ®] [Google Scholar], 1979 Heckman , J. ( 1979 ). Sample selection bias as a specification error . Econometrica 47 : 153161 .[Crossref], [Web of Science ®] [Google Scholar]) to a broad class of nonlinear regression models involving endogenous switching and its two most common incarnations, endogenous sample selection and endogenous treatment effects. The approach should be appealing to applied researchers for three reasons. First, econometric applications involving endogenous switching abound. Secondly, the approach requires neither linearity of the regression function nor full parametric specification of the model. It can, in fact, be applied under the minimal parametric assumptions—i.e., specification of only the conditional means of the outcome and switching variables. Finally, it is amenable to relatively straightforward estimation methods. Examples of applications of the method are discussed.  相似文献   
92.
93.
This article addresses the problem of testing the null hypothesis H0 that a random sample of size n is from a distribution with the completely specified continuous cumulative distribution function Fn(x). Kolmogorov-type tests for H0 are based on the statistics C+ n = Sup[Fn(x)?F0(x)] and C? n=Sup[F0(x)?Fn(x)], where Fn(x) is an empirical distribution function. Let F(x) be the true cumulative distribution function, and consider the ordered alternative H1: F(x)≥F0(x) for all x and with strict inequality for some x. Although it is natural to reject H0 and accept H1 if C + n is large, this article shows that a test that is superior in some ways rejects F0 and accepts H1 if Cmdash n is small. Properties of the two tests are compared based on theoretical results and simulated results.  相似文献   
94.
Hader and Park (1978) introduced second order slope rotatability in axial directions. Park (1987) introduced second order slope rotatabilty over all directions. It is shown that these designs have the additional properly that the sum of the variances of estimates of slopes in all directions at any point is a function of the distance of the point from the design origin.  相似文献   
95.
96.
The problem of estimation of parameters of a mixture of degenerate and exponential distributions is considered. A new sampling scheme is proposed and the exact bias and the mean square error (MSE) of the maximum likelihood estimators of the parameters is derived. Moment estimators, their approximate biases and the MSE are obtained. Asymptotic distributions of the estimators are also obtained for both the cases.  相似文献   
97.
98.
The operating characteristic curves of certain known sigma variables sampling plans may not be satisfactory in that they have a tendency to reject even lots of acceptable quality. This note presents the theory and a method to identify such known sigma variables plans possessing unsatisfactory operating characteristic curves.  相似文献   
99.
A sampling plan is derived for compliance testing providing consumer protection.  相似文献   
100.
In a previous paper. B. R. Rao and Talwalker (1993) considered absolutely continuous life distributions and extended the Lack of Memory Property (L.M.P.) of the exponential distribution and showed that several classes of life distributions have this property, which was called the 'setting the clock back to zero' property. ¶Its analog is discussed in the present paper for hivariate and multivariate classes of life distributions. As a simple application of this analog, it is proved that the Life expectancy and the Percentile Residual Life vectors of a population of individuals under the influence of multiple competing risks have simple expressions if the class of their joint life distributions has the setting the clock back to zero property,  相似文献   
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