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作者：Zhu, Yunzhang; Shen, Xiaotong; Pan, Wei
作者单位：University of Minnesota System; University of Minnesota Twin Cities; University of Minnesota System; University of Minnesota Twin Cities
摘要：Gaussian graphical models are useful to analyze and visualize conditional dependence relationships between interacting units. Motivated from network analysis under different experimental conditions, such as gene networks for disparate cancer subtypes, we model structural changes over multiple networks with possible heterogeneities. In particular, we estimate multiple precision matrices describing dependencies among interacting units through maximum penalized likelihood. Of particular interest ...
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作者：Gu, Kelvin; Pati, Debdeep; Dunson, David B.
作者单位：Stanford University; State University System of Florida; Florida State University; Duke University
摘要：Modeling object boundaries based on image or point cloud data is frequently necessary in medical and scientific applications ranging from detecting tumor contours for targeted radiation therapy, to the classification of organisms based on their structural information. In low-contrast images or sparse and noisy point clouds, there is often insufficient data to recover local segments of the boundary in isolation. Thus, it becomes critical to model the entire boundary in the form of a closed curv...
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作者：Wierzbicki, Michael R.; Guo, Li-Bing; Du, Qing-Tao; Guo, Wensheng
作者单位：University of Pennsylvania; Guangdong Pharmaceutical University
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作者：Du, Pang
作者单位：Virginia Polytechnic Institute & State University
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作者：Hu, Y. J.; Lin, D. Y.; Sun, W.; Zeng, D.
作者单位：Emory University; University of North Carolina; University of North Carolina Chapel Hill
摘要：Copy number variants (CNVs) and single nucleotide polymorphisms (SNPs) coexist throughout the human genome and jointly contribute to phenotypic variations. Thus, it is desirable to consider both types of variants, as characterized by allele-specific copy numbers (ASCNs), in association studies of complex human diseases. Current SNP genotyping technologies capture the CNV and SNP information simultaneously via fluorescent intensity measurements. The common practice of calling ASCNs from the int...
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作者：Rosenthal, Michael; Wu, Wei; Klassen, Eric; Srivastava, Anuj
作者单位：State University System of Florida; Florida State University; State University System of Florida; Florida State University
摘要：This article studies the problem of modeling relationship between two spherical (or directional) random variables in a regression setup. Here the predictor and the response variables are constrained to be on a unit sphere and, due to this nonlinear condition, the standard Euclidean regression models do not apply. Several past papers have studied this problem, termed spherical regression, by modeling the response variable with a von Mises-Fisher (VMF) density with the mean given by a rotation o...
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作者：Mueller, P.; Quintana, F.
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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：Claggett, Brian; Xie, Minge; Tian, Lu
作者单位：Harvard University; Harvard Medical School; Rutgers University System; Rutgers University New Brunswick; Stanford University
摘要：Meta-analysis is a valuable tool for combining information from independent studies. However, most common meta-analysis techniques rely on distributional assumptions that are difficult, if not impossible, to verify. For instance, in the commonly used fixed-effects and random-effects models, we take for granted that the underlying study-level parameters are either exactly the same across individual studies or that they are realizations of a random sample from a population, often under a paramet...
