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作者：Basse, Guillaume; Feller, Avi
作者单位：Harvard University; University of California System; University of California Berkeley
摘要：Two-stage randomization is a powerful design for estimating treatment effects in the presence of interference; that is, when one individual's treatment assignment affects another individual's outcomes. Our motivating example is a two-stage randomized trial evaluating an intervention to reduce student absenteeism in the School District of Philadelphia. In that experiment, households with multiple students were first assigned to treatment or control; then, in treated households, one student was ...
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作者：Karwa, Vishesh
作者单位：University System of Ohio; Ohio State University
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作者：Krupskii, Pavel; Huser, Raphael; Genton, Marc G.
作者单位：King Abdullah University of Science & Technology
摘要：We propose a new copula model that can be used with replicated spatial data. Unlike the multivariate normal copula, the proposed copula is based on the assumption that a common factor exists and affects the joint dependence of all measurements of the process. Moreover, the proposed copula can model tail dependence and tail asymmetry. The model is parameterized in terms of a covariance function that may be chosen from the many models proposed in the literature, such as the Matern model. For som...
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作者：She, Yiyuan; Wang, Zhifeng; Jiang, He
作者单位：State University System of Florida; Florida State University
摘要：Variable selection for models including interactions between explanatory variables often needs to obey certain hierarchical constraints. Weak or strong structural hierarchy requires that the existence of an interaction term implies at least one or both associated main effects to be present in the model. Lately, this problem has attracted a lot of attention, but existing computational algorithms converge slow even with a moderate number of predictors. Moreover, in contrast to the rich literatur...
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作者：Athey, Susan; Eckles, Dean; Imbens, Guido W.
作者单位：Stanford University; National Bureau of Economic Research; Massachusetts Institute of Technology (MIT)
摘要：We study the calculation of exact p-values for a large class of nonsharp null hypotheses about treatment effects in a setting with data from experiments involving members of a single connected network. The class includes null hypotheses that limit the effect of one unit's treatment status on another according to the distance between units, for example, the hypothesis might specify that the treatment status of immediate neighbors has no effect, or that units more than two edges away have no eff...
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作者：Warnick, Ryan; Guindani, Michele; Erhardt, Erik; Allen, Elena; Calhoun, Vince; Vannucci, Marina
作者单位：Rice University; University of California System; University of California Irvine; University of New Mexico; University of New Mexico; University of New Mexico
摘要：Dynamic functional connectivity, that is, the study of how interactions among brain regions change dynamically over the course of an fMRI experiment, has recently received wide interest in the neuroimaging literature. Current approaches for studying dynamic connectivity often rely on ad hoc approaches for inference, with the fMRI time courses segmented by a sequence of sliding windows. We propose a principled Bayesian approach to dynamic functional connectivity, which is based on the estimatio...
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作者：Zhang, Anderson Y.; Zhou, Harrison H.
作者单位：Yale University
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作者：Sun, BaoLuo; Tchetgen, Eric J. Tchetgen
作者单位：Harvard University; Harvard T.H. Chan School of Public Health; Harvard University; Harvard T.H. Chan School of Public Health
摘要：The development of coherent missing data models to account for nonmonotone missing at random (MAR) data by inverse probability weighting (IPW) remains to date largely unresolved. As a consequence, IPW has essentially been restricted for use only in monotone MAR settings. We propose a class of models for nonmonotone missing data mechanisms that spans the MAR model, while allowing the underlying full data law to remain unrestricted. For parametric specifications within the proposed class, we int...
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作者：Cressie, Noel
作者单位：University of Wollongong
摘要：Too much carbon dioxide (CO2) in the atmosphere is a threat to long-term sustainability of Earth's ecosystem. Atmospheric CO2 is a leading greenhouse gas that has increased to levels not seen since the middle Pliocene (approximately 3.6 million years ago). One of the US National Aeronautics Space Administration's (NASA) remote sensing missions is the Orbiting Carbon Observatory-2, whose principal science objective is to estimate the global geographic distribution of CO2 sources and sinks at Ea...
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作者：Dadaneh, Siamak Zamani; Qian, Xiaoning; Zhou, Mingyuan
作者单位：Texas A&M University System; Texas A&M University College Station; University of Texas System; University of Texas Austin; University of Texas System; University of Texas Austin
摘要：We perform differential expression analysis of high-throughput sequencing count data under a Bayesian nonparametric framework, removing sophisticated ad hoc pre-processing steps commonly required in existing algorithms. We propose to use the gamma (beta) negative binomial process, which takes into account different sequencing depths using sample-specific negative binomial probability (dispersion) parameters, to detect differentially expressed genes by comparing the posterior distributions of g...
