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作者：Sohn, Michael B.; Li, Hongzhe
作者单位：University of Pennsylvania
摘要：Motivated by recent advances in causal mediation analysis and problems in the analysis of microbiome data, we consider the setting where the effect of a treatment on an outcome is transmitted through perturbing the microbial communities or compositional mediators. The compositional and high-dimensional nature of such mediators makes the standard mediation analysis not directly applicable to our setting. We propose a sparse compositional mediation model that can be used to estimate the causal d...
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作者：Gu, Chenyang; Gutman, Roee
作者单位：Harvard University; Brown University; Harvard University; Harvard Medical School
摘要：Evaluating and tracking patients' functional status through the post-acute care continuum requires a common instrument. However, different post-acute service providers such as nursing homes, inpatient rehabilitation facilities and home health agencies rely on different instruments to evaluate patients' functional status. These instruments assess similar functional status domains, but they comprise different activities, rating scales and scoring instructions. These differences hinder the compar...
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作者：Petersen, Alexander; Deoni, Sean; Mueller, Hans-Georg
作者单位：University of California System; University of California Santa Cruz; Brown University; University of California System; University of California Davis
摘要：Assessing brain development for small infants is important for determining how the human brain grows during the early period of life when the rate of brain growth is at its peak. The development of MRI techniques has enabled the quantification of brain development. A key quantity that can be extracted from MRI measurements is the level of myelination, where myelin acts as an insulator around nerve fibers and its deployment makes nerve pulse propagation more efficient. The co-variation of myeli...
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作者：Niu, Xiaoyue; Hoff, Peter D.
作者单位：Pennsylvania Commonwealth System of Higher Education (PCSHE); Pennsylvania State University; Pennsylvania State University - University Park; Duke University
摘要：Health exams determine a patient's health status by comparing the patient's measurement with a population reference range, a 95% interval derived from a homogeneous reference population. Similarly, most of the established relation among health problems are assumed to hold for the entire population. We use data from the 2009-2010 National Health and Nutrition Examination Survey (NHANES) on four major health problems in the U.S. and apply a joint mean and covariance model to study how the refere...
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作者：Wang, Lu; Zhang, Zhengwu; Dunson, David
作者单位：Central South University; University of Rochester; Duke University
摘要：This article focuses on the problem of studying shared-and individual-specific structure in replicated networks or graph-valued data. In particular, the observed data consist of n graphs, G(i), i = 1,..., n, with each graph consisting of a collection of edges between V nodes. In brain connectomics, the graph for an individual corresponds to a set of interconnections among brain regions. Such data can be organized as a V x V binary adjacency matrix A(i) for each i, with ones indicating an edge ...
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作者：Li, Tianxi; Levina, Elizaveta; Zhu, Ji
作者单位：University of Virginia; University of Michigan System; University of Michigan
摘要：Prediction algorithms typically assume the training data are independent samples, but in many modern applications samples come from individuals connected by a network. For example, in adolescent health studies of risktaking behaviors, information on the subjects' social network is often available and plays an important role through network cohesion, the empirically observed phenomenon of friends behaving similarly. Taking cohesion into account in prediction models should allow us to improve th...
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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：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...
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作者：Marchetti-Bowick, Micol; Yu, Yaoliang; Wu, Wei; Xing, Eric P.
作者单位：Carnegie Mellon University; University of Waterloo
摘要：In this work, we present a new approach for jointly performing eQTL mapping and gene network inference while encouraging a transfer of information between the two tasks. We address this problem by formulating it as a multiple-output regression task in which we aim to learn the regression coefficients while simultaneously estimating the conditional independence relationships among the set of response variables. The approach we develop uses structured sparsity penalties to encourage the sharing ...
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作者：Katsevich, Eugene; Sabatti, Chiara
作者单位：Stanford University
摘要：We tackle the problem of selecting from among a large number of variables those that are important for an outcome. We consider situations where groups of variables are also of interest. For example, each variable might be a genetic polymorphism, and we might want to study how a trait depends on variability in genes, segments of DNA that typically contain multiple such polymorphisms. In this context, to discover that a variable is relevant for the outcome implies discovering that the larger ent...
