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作者：Watson, Joe; Zidek, James, V; Shaddick, Gavin
作者单位：University of British Columbia; University of Exeter
摘要：This paper presents a general model framework for detecting the preferential sampling of environmental monitors recording an environmental process across space and/or time. This is achieved by considering the joint distribution of an environmental process with a site-selection process that considers where and when sites are placed to measure the process. The environmental process may be spatial, temporal or spatio-temporal in nature. By sharing random effects between the two processes, the joi...
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作者：Lee, Juhee; Thall, Peter F.; Lin, Steven H.
作者单位：University of California System; University of California Santa Cruz; University of Texas System; UTMD Anderson Cancer Center; University of Texas System; UTMD Anderson Cancer Center
摘要：We propose a Bayesian semiparametric joint regression model for a recurrent event process and survival time. Assuming independent latent subject frailties, we define marginal models for the recurrent event process intensity and survival distribution as functions of the subject's frailty and baseline covariates. A robust Bayesian model, called Joint-DP, is obtained by assuming a Dirichlet process for the frailty distribution. We present a simulation study that compares posterior estimates under...
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作者：Schwartzman, Armin; Schork, Andrew J.; Zablocki, Rong; Thompson, Wesley K.
作者单位：University of California System; University of California San Diego; University of California System; University of California San Diego
摘要：Analysis of genome-wide association studies (GWAS) is characterized by a large number of univariate regressions where a quantitative trait is regressed on hundreds of thousands to millions of single-nucleotide polymorphism (SNP) allele counts, one at a time. This article proposes an estimator of the SNP heritability of the trait, defined here as the fraction of the variance of the trait explained by the SNPs in the study. The proposed GWAS heritability (GWASH) estimator is easy to compute, hig...
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作者：Mastrantonio, Gianluca; Lasinio, Giovanna Jona; Pollice, Alessio; Capotorti, Giulia; Teodonio, Lorenzo; Genova, Giulio; Blasi, Carlo
作者单位：Polytechnic University of Turin; Universita degli Studi di Bari Aldo Moro
摘要：We introduce a Bayesian multivariate hierarchical framework to estimate a space-time model for a joint series of monthly extreme temperatures and amounts of precipitation. Data are available for 360 monitoring stations over 60 years, with missing data affecting almost all series. Model components account for spatio-temporal correlation and annual cycles, dependence on covariates and between responses. Spatio-temporal dependence is modeled by the nearest neighbor Gaussian process (GP), response...
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作者：Zhu, Li; Huo, Zhiguang; Ma, Tianzhou; Oesterreich, Steffi; Tseng, George C.
作者单位：Pennsylvania Commonwealth System of Higher Education (PCSHE); University of Pittsburgh; State University System of Florida; University of Florida; University System of Maryland; University of Maryland College Park; Pennsylvania Commonwealth System of Higher Education (PCSHE); University of Pittsburgh; Pennsylvania Commonwealth System of Higher Education (PCSHE); University of Pittsburgh
摘要：Variable selection is a pervasive problem in modern high-dimensional data analysis where the number of features often exceeds the sample size (a.k.a. small-n-large-p problem). Incorporation of group structure knowledge to improve variable selection has been widely studied. Here, we consider prior knowledge of a hierarchical overlapping group structure to improve variable selection in regression setting. In genomics applications, for instance, a biological pathway contains tens to hundreds of g...
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作者：Jun, Seong-Hwan; Wong, Samuel W. K.; Zidek, James, V; Bouchard-Cote, Alexandre
作者单位：University of British Columbia; University of Waterloo
摘要：In this paper, we consider the knot-matching problem arising in computational forestry. The knot-matching problem is an important problem that needs to be solved to advance the state of the art in automatic strength prediction of lumber. We show that this problem can be formulated as a quadripartite matching problem and develop a sequential decision model that admits efficient parameter estimation along with a sequential Monte Carlo sampler on graph matching that can be utilized for rapid samp...
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作者：Euan, Carolina; Sun, Ying; Ombao, Hernando
作者单位：King Abdullah University of Science & Technology
摘要：We develop the hierarchical cluster coherence (HCC) method for brain signals, a procedure for characterizing connectivity in a network by clustering nodes or groups of channels that display a high level of coordination as measured by cluster-coherence. While the most common approach to measure dependence between clusters is through pairs of single time series, our method proposes cluster coherence which measures dependence between pairs of whole clusters rather than between single elements. Th...
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作者：Tipton, John R.; Hooten, Mevin B.; Nolan, Connor; Booth, Robert K.; McLachlan, Jason
作者单位：University of Arkansas System; University of Arkansas Fayetteville; Colorado State University System; Colorado State University Fort Collins; United States Department of the Interior; United States Geological Survey; University of Arizona; Lehigh University; University of Notre Dame
摘要：Multivariate compositional count data arise in many applications including ecology, microbiology, genetics and paleoclimate. A frequent question in the analysis of multivariate compositional count data is what underlying values of a covariate(s) give rise to the observed composition. Learning the relationship between covariates and the compositional count allows for inverse prediction of unobserved covariates given compositional count observations. Gaussian processes provide a flexible framewo...
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作者：Nethery, Rachel C.; Mealli, Fabrizia; Dominici, Francesca
作者单位：Harvard University; Harvard T.H. Chan School of Public Health; University of Florence
摘要：Most causal inference studies rely on the assumption of overlap to estimate population or sample average causal effects. When data suffer from non-overlap, estimation of these estimands requires reliance on model specifications due to poor data support. All existing methods to address non-overlap, such as trimming or down-weighting data in regions of poor data support, change the estimand so that inference cannot be made on the sample or the underlying population. In environmental health resea...
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作者：Berger, Moritz; Wagner, Michael; Schmid, Matthias
作者单位：University of Bonn; University of Bonn; Helmholtz Association; German Center for Neurodegenerative Diseases (DZNE)
摘要：We propose a regression model termed extended GB2 model, which is designed to analyze ratios of biomarkers in epidemiological and medical research. Typical examples of biomarker ratios are given by the LDL/HDL cholesterol ratio in cardiovascular research and the amyloid-beta 42/40 ratio in dementia research. Unlike regression modeling with a log-transformed response, which is often used to describe ratio outcomes in observational studies, the extended GB2 model directly links the expectation o...
