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作者：Xiao, Luo; Thurston, Sally W.; Ruppert, David; Love, Tanzy M. T.; Davidson, Philip W.
作者单位：Johns Hopkins University; University of Rochester; Cornell University; Cornell University; University of Rochester; University of Rochester; University of Rochester
摘要：The Seychelles Child Development Study (SCDS) examines the effects of prenatal exposure to methylmercury on the functioning of the central nervous system. The SCDS data include 20 outcomes measured on 9-year-old children that can be classified broadly in four outcome classes or domains: cognition, memory, motor, and social behavior. Previous analyses and scientific theory suggest that these outcomes may belong to more than one of these domains, rather than only a single domain as is frequently...
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作者：Jones, Bradley; Majumdar, Dibyen
作者单位：University of Antwerp; SAS Institute Inc; University of Illinois System; University of Illinois Chicago; University of Illinois Chicago Hospital
摘要：We consider screening experiments where an investigator wishes to study many factors using fewer observations. Our focus is on experiments with two-level factors and a main effects model with intercept. Since the number of parameters is larger than the number of observations, traditional methods of inference and design are unavailable. In 1959, Box suggested the use of supersaturated designs and in 1962, Booth and Cox introduced measures for efficiency of these designs including E(s(2)), which...
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作者：Zhou, Qing
作者单位：University of California System; University of California Los Angeles
摘要：Regularized linear regression under the l(1) penalty, such as the Lasso, has been shown to be effective in variable selection and sparse modeling. The sampling distribution of an l(1)-penalized estimator (beta) over cap is hard to determine as the estimator is defined by an optimization problem that in general can only be solved numerically and many of its components may be exactly zero. Let S be the subgradient of the (1) norm of the coefficient vector beta evaluated at (beta) over cap. We fi...
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作者：Luo, Shan; Chen, Zehua
作者单位：Shanghai Jiao Tong University; National University of Singapore
摘要：In this article, we propose a method called sequential Lasso (SLasso) for feature selection in sparse high-dimensional linear models. The SLasso selects features by sequentially solving partially penalized least squares problems where the features selected in earlier steps are not penalized. The SLasso uses extended BIC (EBIC) as the stopping rule. The procedure stops when EBIC reaches a minimum. The asymptotic properties of SLasso are considered when the dimension of the feature space is ultr...
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作者：Rosenbaum, Paul R.
作者单位：University of Pennsylvania
摘要：In a nonrandomized or observational study, a weak association between receipt of the treatment and an outcome may be explained not as effects caused by the treatment but rather by a small bias in the assignment of individuals to treatment or control; however, a strong association may be explained as noncausal only by a large bias. The strength of the association between treatment and outcome is not uniform across the data from a study, and this motivates giving greater weight where the associa...
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作者：Wang, Bo; Shi, Jian Qing
作者单位：University of Leicester; Newcastle University - UK
摘要：In this article, we propose a generalized Gaussian process concurrent regression model for functional data, where the functional response variable has a binomial, Poisson, or other non-Gaussian distribution from an exponential family, while the covariates are mixed functional and scalar variables. The proposed model offers a nonparametric generalized concurrent regression method for functional data with multidimensional covariates, and provides a natural framework on modeling common mean struc...
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作者：Lu, Xiaosun; Marron, J. S.; Haaland, Perry
作者单位：University of North Carolina; University of North Carolina Chapel Hill
摘要：This article discusses a study of cell images in cell culture biology from an object-oriented point of view. The motivation of this research is to develop a statistical approach to cell image analysis that better supports the automated development of stem cell growth media. A major hurdle in this process is the need for human expertise, based on studying cells under the microscope, to make decisions about the next step of the cell culture process. We aim to use digital imaging technology coupl...
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作者：Minas, Giorgos; Aston, John A. D.; Stallard, Nigel
作者单位：University of Warwick; University of Warwick
摘要：We present a methodology for dealing with recent challenges in testing global hypotheses using multivariate observations. The proposed tests target situations, often arising in emerging applications of neuroimaging, where the sample size n is relatively small compared with the observations' dimension K. We employ adaptive designs allowing for sequential modifications of the test statistics adapting to accumulated data. The adaptations are optimal in the sense of maximizing the predictive power...
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作者：Percival, Daniel M.; Percival, Donald B.; Denbo, Donald W.; Gica, Edison; Huang, Paul Y.; Mofjeld, Harold O.; Spillane, Michael C.
作者单位：Alphabet Inc.; Google Incorporated; University of Washington; University of Washington Seattle; University of Washington; University of Washington Seattle; University of Washington; University of Washington Seattle; National Oceanic Atmospheric Admin (NOAA) - USA; National Oceanic Atmospheric Admin (NOAA) - USA
摘要：In response to hazards posed by earthquake-induced tsunamis, the National Oceanographic and Atmospheric Administration developed a system for issuing timely warnings to coastal communities. This system, in part, involves matching data collected in real time from deep-ocean buoys to a database of precomputed geophysical models, each associated with a geographical location. Currently, trained operators must handpick models from the database using the epicenter of the earthquake as guidance, whic...
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作者：Efron, Bradley
作者单位：Stanford University
摘要：Classical statistical theory ignores model selection in assessing estimation accuracy. Here we consider bootstrap methods for computing standard errors and confidence intervals that take model selection into account. The methodology involves bagging, also known as bootstrap smoothing, to tame the erratic discontinuities of selection-based estimators. A useful new formula for the accuracy of bagging then provides standard errors for the smoothed estimators. Two examples, nonparametric and param...
