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作者:Wang, Chao; Liu, Heng; Yao, Jian-feng; Davis, Richard A.; Li, Wai Keung
作者单位:University of Hong Kong; Alphabet Inc.; Google Incorporated; Columbia University
摘要:This article studies theory and inference of an observation-driven model for time series of counts. It is assumed that the observations follow a Poisson distribution conditioned on an accompanying intensity process, which is equipped with a two-regime structure according to the magnitude of the lagged observations. Generalized from the Poisson autoregression, it allows more flexible, and even negative correlation, in the observations, which cannot be produced by the single-regime model. Classi...
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作者:Allen, Genevera I.; Grosenick, Logan; Taylor, Jonathan
作者单位:Rice University; Rice University; Baylor College of Medicine; Baylor College Medical Hospital; Baylor College of Medicine; Baylor College Medical Hospital; Stanford University; Stanford University
摘要:Variables in many big-data settings are structured, arising, for example, from measurements on a regular grid as in imaging and time series or from spatial-temporal measurements as in climate studies. Classical multivariate techniques ignore these structural relationships often resulting in poor performance. We propose a generalization of principal components analysis (PCA) that is appropriate for massive datasets with structured variables or known two-way dependencies. By finding the best low...
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作者:Joyce, Patrick M.; Malec, Donald; Little, Roderick J. A.; Gilary, Aaron; Navarro, Alfredo; Asiala, Mark E.
作者单位:Centers for Disease Control & Prevention - USA; CDC National Center for Health Statistics (NCHS); University of Michigan System; University of Michigan
摘要:Section 203 of the Voting Rights Act includes provisions requiring the use of election materials in languages other than English for states or political subdivisions, specifically, when a minimum number of voting age U.S. citizens of specified language minority groups who are unable to speak English very well and have obtained less than a fifth-grade education is met. Data on these characteristics are provided by the 2010 Census and the American Community Survey (ACS), a general purpose sample...
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作者:Wei, Susan; Kosorok, Michael R.
作者单位:University of North Carolina; University of North Carolina Chapel Hill; University of North Carolina; University of North Carolina Chapel Hill
摘要:This article introduces a new machine learning task, called latent supervised learning, where the goal is to learn a binary classifier from continuous training labels that serve as surrogates for the unobserved class labels. We investigate a specific model where the surrogate variable arises from a two-component Gaussian mixture with unknown means and variances, and the component membership is determined by a hyperplane in the covariate space. The estimation of the separating hyperplane and th...
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作者:Zhao, Lihui; Tian, Lu; Cai, Tianxi; Claggett, Brian; Wei, L. J.
作者单位:Northwestern University; Stanford University; Harvard University; Harvard University; Harvard Medical School
摘要:When comparing a new treatment with a control in a randomized clinical study, the treatment effect is generally assessed by evaluating a summary measure over a specific study population. The success of the trial heavily depends on the choice of such a population. In this article, we show a systematic, effective way to identify a promising population, for which the new treatment is expected to have a desired benefit, using the data from a current study involving similar comparator treatments. S...
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作者:Garcia-Donato, G.; Martinez-Beneito, M. A.
作者单位:Universidad de Castilla-La Mancha; CIBER - Centro de Investigacion Biomedica en Red; CIBERESP
摘要:One important aspect of Bayesian model selection is how to deal with huge model spaces, since the exhaustive enumeration of all the models entertained is not feasible and inferences have to be based on the very small proportion of models visited. This is the case for the variable selection problem with a moderately large number of possible explanatory variables considered in this article. We review some of the strategies proposed in the literature, from a theoretical point of view using argume...
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作者:Chen, Huaihou; Wang, Yuanjia; Paik, Myunghee Cho; Choi, H. Alex
作者单位:New York University; Columbia University; Seoul National University (SNU); University of Texas System; University of Texas Health Science Center Houston
摘要:Multilevel functional data are collected in many biomedical studies. For example, in a study of the effect of Nimodipine on patients with subarachnoid hemorrhage (SAH), patients underwent multiple 4-hr treatment cycles. Within each treatment cycle, subjects' vital signs were reported every 10 min. These data have a natural multilevel structure with treatment cycles nested within subjects and measurements nested within cycles. Most literature on nonparametric analysis of suchmultilevel function...
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作者:Galvao, Antonio F.; Lamarche, Carlos; Lima, Luiz Renato
作者单位:University of Iowa; University of Kentucky; University of Tennessee System; University of Tennessee Knoxville; Universidade Federal da Paraiba
摘要:This article investigates estimation of censored quantile regression (QR) models with fixed effects. Standard available methods are not appropriate for estimation of a censored QR model with a large number of parameters or with covariates correlated with unobserved individual heterogeneity. Motivated by these limitations, the article proposes estimators that are obtained by applying fixed effects QR to subsets of observations selected either parametrically or nonparametrically. We derive the l...
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作者:Wang, Yuanjia; Chen, Huaihou; Zeng, Donglin; Mauro, Christine; Duan, Naihua; Shear, M. Katherine
作者单位:Columbia University; New York University; University of North Carolina; University of North Carolina Chapel Hill; Columbia University; Columbia University; Columbia University
摘要:Constructing classification rules for accurate diagnosis of a disorder is an important goal in medical practice. In many clinical applications, there is no clinically significant anatomical or physiological deviation that exists to identify the gold standard disease status to inform development of classification algorithms. Despite the absence of perfect disease class identifiers, there are usually one or more disease-informative auxiliary markers along with feature variables that comprise kno...
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作者:Zhang, Ting
作者单位:University of Iowa
摘要:This article considers the problem of clustering high-dimensional time series based on trend parallelism. The underlying process is modeled as a nonparametric trend function contaminated by locally stationary errors, a special class of nonstationary processes. For each group where the parallelism holds, I semiparametrically estimate its representative trend function and vertical shifts of group members, and establish their central limit theorems. An information criterion, consisting of in-grou...