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作者：Hare, Eric; Hofmann, Heike; Carriquiry, Alicia
作者单位：Iowa State University; Iowa State University
摘要：In 2009, the National Academy of Sciences published a report questioning the scientific validity of many forensic methods including firearm examination. Firearm examination is a forensic tool used to help the court determine whether two bullets were fired from the same gun barrel. During the firing process, rifling, manufacturing defects, and impurities in the barrel create striation marks on the bullet. Identifying these striation markings in an attempt to match two bullets is one of the prim...
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作者：Rad, Kamiar Rahnama; Machado, Timothy A.; Paninski, Liam
作者单位：City University of New York (CUNY) System; Baruch College (CUNY); Columbia University; Columbia University
摘要：A common analytical problem in neuroscience is the interpretation of neural activity with respect to sensory input or behavioral output. This is typically achieved by regressing measured neural activity against known stimuli or behavioral variables to produce a tuning function for each neuron. Unfortunately, because this approach handles neurons individually, it cannot take advantage of simultaneous measurements from spatially adjacent neurons that often have similar tuning properties. On the ...
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作者：Zhou, Xiang
作者单位：University of Michigan System; University of Michigan
摘要：Linear mixed models (LMMs) are among the most commonly used tools for genetic association studies. However, the standard method for estimating variance components in LMMs-the restricted maximum likelihood estimation method (REML)-suffers from several important drawbacks: REML requires individual-level genotypes and phenotypes from all samples in the study, is computationally slow, and produces downward-biased estimates in case control studies. To remedy these drawbacks, we present an alternati...
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作者：Wang, Y. Samuel; Matsueda, Ross L.; Erosheva, Elena A.
作者单位：University of Washington; University of Washington Seattle; University of Washington; University of Washington Seattle
摘要：In this article, we consider modeling ranked responses from a heterogeneous population. Specifically, we analyze data from the Eurobarometer 34.1 survey regarding public policy preferences toward drugs, alcohol, and AIDS. Such policy preferences are likely to exhibit substantial differences within as well as across European nations reflecting a wide variety of cultures, political affiliations, ideological perspectives, and common practices. We use a mixed membership model to account for multip...
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作者：Zhu, Xiang; Stephens, Matthew
作者单位：University of Chicago; University of Chicago
摘要：Bayesian methods for large-scale multiple regression provide attractive approaches to the analysis of genome-wide association studies (GWAS). For example, they can estimate heritability of complex traits, allowing for both polygenic and sparse models; and by incorporating external genomic data into the priors, they can increase power and yield new biological insights. However, these methods require access to individual genotypes and phenotypes, which are often not easily available. Here we pro...
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作者：Quick, Harrison; Waller, Lance A.; Casper, Michele
作者单位：Drexel University; Emory University; Centers for Disease Control & Prevention - USA
摘要：Geographic patterns in stroke mortality have been studied as far back as the 1960s when a region of the southeastern United States became known as the stroke belt due to its unusually high rates. While stroke mortality rates are known to increase exponentially with age, an investigation of spatiotemporal trends by age group at the county level is daunting due to the preponderance of small population sizes and/or few stroke events by age group. In this paper, we implement a multivariate space-t...
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作者：Cagnone, Silvia; Giannerini, Simone; Modugno, Lucia
作者单位：University of Bologna
摘要：In this paper, we introduce a multilevel specification with stochastic volatility for repeated cross-sectional data. Modelling the time dynamics in repeated cross sections requires a suitable adaptation of the multilevel framework where the individuals/items are modelled at the first level whereas the time component appears at the second level. We perform maximum likelihood estimation by means of a nonlinear state space approach combined with Gauss-Legendre quadrature methods to approximate th...
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作者：Tak, Hyungsuk; Mandel, Kaisey; Van Dyk, David A.; Kashyap, Vinay L.; Meng, Xiao-Li; Siemiginowska, Aneta
作者单位：Smithsonian Astrophysical Observatory; Smithsonian Institution; Harvard University; Harvard University; Imperial College London
摘要：The gravitational field of a galaxy can act as a lens and deflect the light emitted by a more distant object such as a quasar. Strong gravitational lensing causes multiple images of the same quasar to appear in the sky. Since the light in each gravitationally lensed image traverses a different path length from the quasar to the Earth, fluctuations in the source brightness are observed in the several images at different times. The time delay between these fluctuations can be used to constrain c...
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作者：Monti, Ricardo Pio; Anagnostopoulos, Christoforos; Montana, Giovanni
作者单位：Imperial College London; Imperial College London; Guy's & St Thomas' NHS Foundation Trust; University of London; King's College London
摘要：In neuroimaging data analysis, Gaussian graphical models are often used to model statistical dependencies across spatially remote brain regions known as functional connectivity. Typically, data is collected across a cohort of subjects and the scientific objectives consist of estimating population and subject-specific connectivity networks. A third objective that is often overlooked involves quantifying inter-subject variability, and thus identifying regions or subnetworks that demonstrate hete...
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作者：Antonelli, Joseph; Schwartz, Joel; Kloog, Itai; Coull, Brent A.
作者单位：Harvard University; Harvard T.H. Chan School of Public Health; Ben-Gurion University of the Negev
摘要：Fine particulate matter (PM2.5) measured at a given location is a mix of pollution generated locally and pollution traveling long distances in the atmosphere. Therefore, the identification of spatial scales associated with health effects can inform on pollution sources responsible for these effects, resulting in more targeted regulatory policy. Recently, prediction methods that yield high-resolution spatial estimates of PM2.5 exposures allow one to evaluate such scale-specific associations. We...
