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作者：Datta, Abhirup; Banerjee, Sudipto; Finley, Andrew O.; Gelfand, Alan E.
作者单位：University of California System; University of California Los Angeles
摘要：Spatial process models for analyzing geostatistical data entail computations that become prohibitive as the number of spatial locations beconne large. This article develops a class of highly scalable nearest-neighbor Gaussian process (NNGP) models to provide fully model-based inference for large geostatistical datasets. We establish that the NNGP is a well-defined spatial process providing legitimate finite-dimensional Gaussian densities with sparse precision matrices. We embed the NNGP as a s...
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作者：Fox, Eric W.; Short, Martin B.; Schoenberg, Frederic P.; Coronges, Kathryn D.; Bertozzi, Andrea L.
作者单位：University of California System; University of California Los Angeles
摘要：We propose various self-exciting point process models for the times when e-mails are sent between individuals in a social network. Using an expectation maximization (EM)-type approach, we fit these models to an e-mail network dataset from West Point Military Academy and the Enron e-mail dataset. We argue that the self-exciting models adequately capture major temporal clustering features in the data and perform better than traditional stationary Poisson models. We also investigate how accountin...
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作者：Oates, Chris J.; Papamarkou, Theodore; Girolami, Mark
作者单位：University of Technology Sydney
摘要：Approximation of the model evidence is well known to be challenging. One promising approach is based on thermodynamic integration, but a key concern is that the thermodynamic integral can suffer from high variability in many applications. This article considers the reduction of variance that can be achieved by exploiting control variates in this setting. Our methodology applies whenever the gradient of both the log likelihood and the log-prior with respect to the parameters can be efficiently ...
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作者：Zhang, Lin; Baladandayuthapani, Veerabhadran; Zhu, Hongxiao; Baggerly, Keith A.; Majewski, Tadeusz; Czerniak, Bogdan A.; Morris, Jeffrey S.
作者单位：University of Texas System; UTMD Anderson Cancer Center
摘要：We develop a functional conditional autoregressive (CAR) model for spatially correlated data for which functions are collected on areal units of a lattice. Our model performs functional- response regression while accounting for spatial correlations with potentially nonseparable and nonstationary covariance structure, in both the space and functional domains. We show theoretically that our construction leads to a CAR model at each functional location, with spatial covariance parameters varying ...
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作者：Brown, Lawrence D.; Johnson, Kory D.
作者单位：University of Pennsylvania
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作者：Cervone, Daniel; D'Amour, Alex; Bornn, Luke; Goldsberry, Kirk
作者单位：New York University
摘要：Basketball games evolve continuously in space and time as players constantly interact with their teammates, the opposing team, and the ball. However, current analyses of basketball outcomes rely on discretized summaries of the game that reduce such interactions to tallies of points, assists, and similar events. In this article, we propose a framework for using optical player tracking data to estimate, in real time, the expected number of points obtained by the end of,a possession. This quantit...
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作者：Da Silva, Damiao Nobrega; Skinner, Chris; Kim, Jae Kwang
作者单位：Universidade Federal do Rio Grande do Norte
摘要：Paradata refers here to data at unit level on an observed auxiliary variable, not usually of direct scientific interest, which may be informative about the quality of the survey data for the unit. There is increasing interest among survey researchers in how to use such data. Its use to reduce bias from nonresponse has received more attention so far than its use to correct for measurement error. This article considers the latter with a focus on binary paradata indicating the presence of measure...
