2006

最新文章

• Algorithms for constructing combined strata variance estimators AI翻译
  作者：Lu, Wilson W.; Brick, J. Michael; Sitter, Randy R.
  作者单位：Westat; Simon Fraser University
  摘要：A jackknife or balanced repeated replication variance estimator in a large survey typically requires a large number of replicates and replicate weights. Reducing the number of replicates may have important advantages for computations and for limiting the risk of data disclosure from public use data files. This article proposes algorithms adapted from scheduling theory to combine variance strata and, thus, reduce the number of replicates. The algorithms are simple and efficient and can be adapt...
• Inference on the number of species through geometric lower bounds AI翻译
  作者：Mao, Chang Xuan
  作者单位：University of California System; University of California Riverside
  摘要：Estimating the number of species in a population from a sample of individuals is investigated in a nonparametric Poisson mixture model. A sequence of lower bounds to the odds that a species is unseen in the sample are proposed from a geometric perspective. A lower bound and its representing mixing distribution can be computed by linear programming with guaranteed convergence. These lower bounds can be estimated by the maximum likelihood method and used to construct lower confidence limits for ...
• Estimation in multiple-frame surveys AI翻译
  作者：Lohr, Sharon; Rao, J. N. K.
  作者单位：Arizona State University; Arizona State University-Tempe; Carleton University
  摘要：Multiple-frame surveys are commonly used to decrease costs of sampling or to reduce undercoverage that could occur if only one sampling frame were used. We describe potential uses and examples of multiple-frame surveys. We then derive optimal linear estimators and pseudomaximum likelihood estimators for the population total when samples are taken independently from each frame using probability sampling designs. We explore the properties of these estimators theoretically and through a simulatio...
• Doubly robust estimation of the area under the receiver-operating characteristic curve in the presence of verification bias AI翻译
  作者：Rotnitzky, Andrea; Faraggi, David; Schisterman, Enrique
  作者单位：Universidad Torcuato Di Tella; Harvard University; Harvard T.H. Chan School of Public Health; University of Haifa; National Institutes of Health (NIH) - USA; NIH Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD)
  摘要：The area under the receiver operating characteristic curve (AUC) is a popular summary measure of the efficacy of a medical diagnostic test to discriminate between healthy and diseased subjects. A frequently encountered problem in studies that evaluate a new diagnostic test is that not all patients undergo disease verification because the verification test is expensive, invasive, or both. Furthermore, the decision to send patients to verification often depends on the new test and on other predi...
• Bayesian wombling: Curvilinear gradient assessment under spatial process models AI翻译
  作者：Banerjee, Sudipto; Gelfand, Alan E.
  作者单位：University of Minnesota System; University of Minnesota Twin Cities; Duke University
  摘要：Large-scale inference for random spatial surfaces over a region using spatial process models has been well studied. Under such models, local analysis of the surface (e.g., gradients at given points) has received recent attention. A more ambitious objective is to move from points to curves, to attempt to assign a meaningful gradient to a curve. For a point, if the gradient in a particular direction is large (positive or negative), then the surface is rapidly increasing or decreasing in that dir...
• Generalized poststratification and importance sampling for subsampled Markov chain Monte Carlo estimation AI翻译
  作者：Guha, Subharup; MacEachern, Steven N.
  作者单位：University System of Ohio; Ohio State University
  摘要：Benchmark estimation is motivated by the goal of producing an approximation to a posterior distribution that is better than the empirical distribution function. This is accomplished by incorporating additional information into the construction of the approximation. We focus here on generalized poststratification, the most successful implementation of benchmark estimation in our experience. We develop generalized poststratification for settings where the source of the simulation differs from th...
• Likelihood subgradient densities AI翻译
  作者：Nygren, Kjell; Nygren, Lan Ma
  作者单位：Rider University
  摘要：We introduce likelihood subgradient densities and explore their basic properties. Using mixtures of likelihood subgradient densities, we propose an approach for constructing tight enveloping functions in the Bayesian context. In the case of normal priors with normal data, the area underneath the resulting enveloping function is bounded above by 2/root pi approximate to 1.128. The approach is extended to k-dimensional models where the corresponding bound is (2/root pi)(k). More generally, our a...
• A Bayesian approach for clustered longitudinal ordinal outcome with nonignorable missing data: Evaluation of an asthma education program AI翻译
  作者：Kaciroti, Niko A.; Raghunathan, Trivellore E.; Schork, M. Anthony; Clark, Noreen M.; Gong, Molly
  作者单位：University of Michigan System; University of Michigan; University of Michigan System; University of Michigan; University of Michigan System; University of Michigan
  摘要：Asthma, a chronic inflammatory disease of the airways, affects an estimated 6.3 million children under age 18 in the United States. A key to successful asthma management, and hence improved quality of life (QOL), calls for an active partnership between asthma patients and their health care providers. To foster this partnership, an intervention program was designed and evaluated using a randomized longitudinal study. The study focused on several outcomes where typically missing data remained a ...
• A reference-free Cuscore chart for dynamic mean change detection and a unified framework for charting performance comparison AI翻译
  作者：Han, D; Tsung, FG
  作者单位：Shanghai Jiao Tong University; Hong Kong University of Science & Technology
  摘要：To detect and estimate nonconstant, time-varying mean shifts, statistical process control (SPC) tools, such as the cumulative score (Cuscore) and generalized likelihood ratio test (GLRT) charts, have recently been proposed. However, their efficiency is based on previous and exact knowledge of a reference pattern. In this article a reference-free Cuscore (RFCuscore) chart is proposed that can trace and detect dynamic mean changes quickly without knowing the reference pattern. In addition, a uni...
• The adaptive lasso and its oracle properties AI翻译
  作者：Zou, Hui
  作者单位：University of Minnesota System; University of Minnesota Twin Cities
  摘要：The lasso is a popular technique for simultaneous estimation and variable selection. Lasso variable selection has been shown to be consistent under certain conditions. In this work we derive a necessary condition for the lasso variable selection to be consistent. Consequently, there exist certain scenarios where the lasso is inconsistent for variable selection. We then propose a new version of the lasso, called the adaptive lasso, where adaptive weights are used for penalizing different coeffi...