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作者：MULRY, MH; SPENCER, BD
作者单位：Northwestern University
摘要：In July 1991 the Census Bureau recommended to its parent agency, the Department of Commerce, that the 1990 census be adjusted for undercount. The Secretary of Commerce decided not to adjust, however. Those decisions relied at least partly on the Census Bureau's analyses of the accuracy of the census and of the proposed undercount adjustments based on-the Post-Enumeration Survey (PES). Error distributions for the nation, states, and smaller geographic units were estimated with extensions of met...
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作者：BURR, D; DOSS, H
摘要：Let xi(p)(x) be the pth quantile of the distribution of the life length of an individual with covariate vector x in the Cox model. We introduce an estimator xi(p)(x) of xi(p)(x) and develop several families of confidence bands for xi(p)(x) as a function of x. To construct one type of band, we proceed as follows. We show that as n --> infinity, where n is the number of individuals in the study, square-root n (xi(p)(x) - xi(p)(x)) converges weakly to a Gaussian process W(x) with a complicated co...
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作者：DEANGELIS, D; HALL, P; YOUNG, GA
作者单位：Australian National University; Commonwealth Scientific & Industrial Research Organisation (CSIRO); University of Cambridge
摘要：Edgeworth and bootstrap approximations to estimator distributions in L1 regression are described. Analytic approximations based on Edgeworth expansions that mix lattice and nonlattice components and allow for an intercept term in the regression are developed under mild conditions, which do not even require a density for the error distribution. Under stronger assumptions on the error distribution, the Edgeworth expansion assumes a simpler form. Bootstrap approximations are described, and the co...
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作者：LEGER, C; ALTMAN, N
作者单位：Cornell University
摘要：Variable selection techniques are often used in combination with multiple linear regression to produce a parsimonious model that fits the data well. It is clearly undesirable for the final model to depend strongly on the inclusion of a few influential cases in the data set. This article discusses a measure of influence of single cases on the final model. based on a similar measure used in ordinary multiple regression. When variables are selected objectively, deletion of individual cases can st...
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作者：BUNGE, J; FITZPATRICK, M
摘要：How many kinds are there? Suppose that a population is partitioned into C classes. In many situations interest focuses not on estimation of the relative sizes of the classes, but on estimation of C itself. For example, biologists and ecologists may be interested in estimating the number of species in a population of plants or animals, numismatists may be concerned with estimating the number of dies used to produce an ancient coin issue, and linguists may be interested in estimating the size of...
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作者：LIN, DY; YING, Z
作者单位：University of Illinois System; University of Illinois Urbana-Champaign
摘要：This article provides a general solution to the problem of missing covariate data under the Cox regression model. The estimating function for the vector of regression parameters is an approximation to the partial likelihood score function with full covariate measurements and reduces to the pseudolikelihood score function of Self and Prentice in the special setting of case-cohort designs. The resulting parameter estimator is consistent and asymptotically normal with a covariance matrix for whic...
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作者：HEIBERGER, RM; BHAUMIK, DK; HOLLAND, B
作者单位：University of South Alabama
摘要：Consider an experiment where the factors are measured on a continuous scale, and suppose that the experimenter is permitted to augment the existing observations with one or more new data points. Bondar's universal optimality criterion (U optimality) suggests that the problem is best studied in the eigenvector coordinate system. We proceed by showing how to construct new points that first equate and then jointly increase the smaller eigenvalues of the crossproduct of the independent variables. ...
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作者：TANG, B
摘要：In this article, we use orthogonal arrays (OA's) to construct Latin hypercubes. Besides preserving the univariate stratification properties of Latin hypercubes, these strength r OA-based Latin hypercubes also stratify each r-dimensional margin. Therefore, such OA-based Latin hypercubes provide more suitable designs for computer experiments and numerical integration than do general Latin hypercubes. We prove that when used for integration, the sampling scheme with OA-based Latin hypercubes offe...
