-
作者：Kooperberg, C; Bose, S; Stone, CJ
作者单位：Indian Statistical Institute; Indian Statistical Institute Kolkata; University of California System; University of California Berkeley
摘要：An automatic procedure that uses linear splines and their tensor products is proposed for fitting a regression model to data involving a polychotomous response variable and one or more predictors. The fitted model can be used for multiple classification. The automatic fitting procedure involves maximum likelihood estimation, stepwise addition, stepwise deletion, and model selection by the Akaike information criterion, cross-validation, or an independent test set. A modified version of the algo...
-
作者：Brunner, E; Dette, H; Munk, A
作者单位：University of Gottingen; Ruhr University Bochum
摘要：Linear rank statistics in nonparametric factorial designs are asymptotically normal and, in general, heteroscedastic. In a comprehensive simulation study, the asymptotic chi-squared law of the corresponding quadratic forms is shown to be a rather poor approximation of the finite-sample distribution. Motivated by this problem, we propose simple finite-sample size approximations for the distribution of quadratic forms in factorial designs under a normal heteroscedastic error structure. These app...
-
作者：Waller, LA; Carlin, BP; Xia, H; Gelfand, AE
作者单位：University of Connecticut
摘要：Maps of regional morbidity and mortality rates are useful tools in determining spatial patterns of disease. Combined with sociodemographic census information, they also permit assessment of environmental justice; that is, whether certain subgroups suffer disproportionately from certain diseases or other adverse effects of harmful environmental exposures. Bayes and empirical Bayes methods have proven useful in smoothing crude maps of disease risk, eliminating the instability of estimates in low...
-
作者：Durazo-Arvizu, R; McGee, D; Li, ZH; Cooper, R
作者单位：Mayo Clinic; Loyola University Chicago
摘要：Many studies have demonstrated a nonmonotonic relationship between mortality and body mass index (BMI), with excess mortality occurring at both low and high levels. Although much discussion and many different analyses have appeared, to our knowledge no attempt has been made to quantitatively establish the BMI at which minimum mortality (BMImin) occurs or to establish confidence intervals for this BMI, accounting for the asymmetry of the relationship. We model the nonmonotonic relationship betw...
-
作者：Monahan, J; Genz, A
作者单位：Washington State University
摘要：The common numerical problem in Bayesian analysis is the numerical integration of the posterior. In high dimensions, this problem becomes too formidable for tired quadrature methods, and Monte Carlo integration is the usual approach. Through the use of modal standardization and a spherical-radial transformation, we reparameterize in terms of a radius r and point z on the surface of the sphere in d dimensions. We propose two types of methods for spherical-radial integration. A completely random...
-
作者：Nandram, B; Sedransk, J; Smith, SJ
作者单位：University System of Ohio; Case Western Reserve University; Fisheries & Oceans Canada; Bedford Institute of Oceanography
摘要：The management of a commercial fishery often requires estimates of the age composition. These estimates are typically based on age and length data obtained from sampling the commercial landings from the fishery and the catches from a research vessel survey. We use data from annual research cruises of Georges Bank conducted by the Canadian Department of Fisheries and Oceans to show how inferences for Atlantic cod (Gadus morhua) can be improved. Traditionally, two-phase stratified sampling is us...
-
作者：Liu, RY; Singh, K
摘要：In this article we propose some new notions of limiting P values for hypothesis testing. The limiting P value (LP) here not only provides the usual attractive interpretation of a P value as the strength in support of the null hypothesis coming from the observed data, but also has several advantages. First, it allows us to resample directly from the empirical distribution (in the bootstrap implementations), rather than from the estimated population distribution satisfying the null constraints. ...
-
作者：Strawderman, RL; Wells, MT
作者单位：University of Michigan System; University of Michigan; Cornell University
摘要：In clinical trials and other settings, confidence intervals for survival probabilities at a fixed point in time are often required. Typically, such intervals are constructed on the cumulative hazard scale; the quantiles required for computing these intervals are generally obtained using a first-order normal theory approximation. The appropriateness of such intervals for small sample sizes or under moderate to heavy censoring is suspect. We demonstrate that significant improvement is possible f...
-
作者：Albert, J; Chib, S
作者单位：Washington University (WUSTL)
摘要：Consider the conditionally independent hierarchical model (CIHM) in which observations yi are independently distributed from f(y(i)/theta(i)), the parameters theta(i) are independently distributed from distributions g(theta/lambda), and the hyperparameters lambda are distributed according to a distribution h(lambda). The posterior distribution of all parameters of the CIHM can be efficiently simulatedby Markov chain Monte Carlo (MCMC) algorithms. Although these simulation algorithms have facil...
-
作者：Kallenberg, WCM; Ledwina, T
作者单位：Wroclaw University of Science & Technology
摘要：In recent years several authors have recommended smooth tests for resting goodness of fit. However, the number of components in the smooth test statistic should be chosen well; otherwise, considerable loss of power may occur. Schwarz's selection rule provides one such good choice. Earlier results on simple null hypotheses are extended here to composite hypotheses, which tend to be of mure practical interest. For general composite hypotheses, consistency of the data-driven smooth tests holds at...
