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作者：Gu, Mengyang; Berger, James O.
作者单位：Duke University; King Abdulaziz University
摘要：We consider the problem of emulating (approximating) computer models (simulators) that produce massive output. The specific simulator we study is a computer model of volcanic pyroclastic flow, a single run of which produces up to 10(9) outputs over a space-time grid of coordinates. An emulator (essentially a statistical model of the simulator-we use a Gaussian Process) that is computationally suitable for such massive output is developed and studied from practical and theoretical perspectives....
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作者：Liu, Yang; Zidek, James V.; Trites, Andrew W.; Battaile, Brian C.
作者单位：University of British Columbia; University of British Columbia
摘要：Bayesian Melding (BM) and downscaling are two Bayesian approaches commonly used to combine data from different sources for statistical inference. We extend these two approaches to combine accurate but sparse direct observations with another set of high-resolution but biased calculated observations. We use our methods to estimate the path of a moving or evolving object and apply them in a case study of tracking northern fur seals. To make the BM approach computationally feasible for high-dimens...
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作者：Rashid, Naim U.; Sun, Wei; Ibrahim, Joseph G.
作者单位：University of North Carolina; University of North Carolina Chapel Hill; Fred Hutchinson Cancer Center
摘要：Sequencing techniques have been widely used to assess gene expression (i.e., RNA-seq) or the presence of epigenetic features (e.g., DNase-seq to identify open chromatin regions). In contrast to traditional microarray platforms, sequencing data are typically summarized in the form of discrete counts, and they are able to delineate allele-specific signals, which are not available from microarrays. The presence of epigenetic features are often associated with gene expression, both of which have b...
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作者：Inacio de Carvalho, Vanda; de Carvalho, Miguel; Alonzo, Todd A.; Gonzalez-Manteiga, Wenceslao
作者单位：Pontificia Universidad Catolica de Chile; University of Southern California; Universidade de Santiago de Compostela
摘要：Due to recent advances in technology, medical diagnosis data are becoming increasingly complex and, nowadays, applications where measurements are curves or images are ubiquitous. Motivated by the need of modeling a functional covariate on a metabolic syndrome case study, we develop a nonparametric functional regression model for the area under the specificity receiver operating characteristic curve. This partial area is a meaningful summary measure of diagnostic accuracy for cases in which mis...
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作者：Deng, Ke; Li, Yang; Zhu, Weiping; Liu, Jun S.
作者单位：Tsinghua University; Harvard University; Australian Defense Force Academy; Australian Defense Force Academy; University of New South Wales Sydney
摘要：As a technique to investigate link-level loss rates of a computer network with low operational cost, loss tomography has received considerable attentions in recent years. A number of parameter estimation methods have been proposed for loss tomography of networks with a tree structure as well as a general topological structure. However, these methods suffer from either high computational cost or insufficient use of information in the data. In this paper, we provide both theoretical results and ...
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作者：Liu, Ying; Wang, Yuanjia; Feng, Yang; Wall, Melanie M.
作者单位：Columbia University; Columbia University
摘要：We propose a Multiple Imputation Random Lasso (MIRL) method to select important variables and to predict the outcome for an epidemiological study of Eating and Activity in Teens. In this study 80% of individuals have at least one variable missing. Therefore, using variable selection methods developed for complete data after listwise deletion substantially reduces prediction power. Recent work on prediction models in the presence of incomplete data cannot adequately account for large numbers of...
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作者：Zhai, Yongliang; Bouchard-Cote, Alexandre
作者单位：University of British Columbia
摘要：We introduce a new inference method to estimate evolutionary distances for any two populations to their most recent common ancestral population using single-nucleotide polymorphism allele frequencies. Our model takes fixation into consideration, making it nonreversible, and guarantees that the distribution of reconstructed ancestral frequencies is contained on the interval [0, 1]. To scale this method to large numbers of populations, we introduce the asymmetric neighbor joining algorithm, an e...
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作者：Chekouo, Thierry; Stingo, Francesco C.; Guindani, Michele; Do, Kim-Anh
作者单位：University of Minnesota System; University of Minnesota Duluth; University of Minnesota Twin Cities; University of Minnesota Hospital; University of Florence; University of California System; University of California Irvine; University of Texas System; UTMD Anderson Cancer Center
摘要：Imaging genetics has rapidly emerged as a promising approach for investigating the genetic determinants of brain mechanisms that underlie an individual's behavior or psychiatric condition. In particular, for early detection and targeted treatment of schizophrenia, it is of high clinical relevance to identify genetic variants and imaging-based biomarkers that can be used as diagnostic markers, in addition to commonly used symptom-based assessments. By combining single-nucleotide polymorphism (S...
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作者：Chang, Won; Haran, Murali; Applegate, Patrick; Pollard, David
作者单位：University System of Ohio; University of Cincinnati; Pennsylvania Commonwealth System of Higher Education (PCSHE); Pennsylvania State University; Pennsylvania State University - University Park; Pennsylvania Commonwealth System of Higher Education (PCSHE); Pennsylvania State University; Pennsylvania State University - University Park
摘要：Human-induced climate change may cause significant ice volume loss from the West Antarctic Ice Sheet (WAIS). Projections of ice volume change from ice sheet models and corresponding future sea-level rise have large uncertainties due to poorly constrained input parameters. In most future applications to date, model calibration has utilized only modern or recent (decadal) observations, leaving input parameters that control the long-term behavior of WAIS largely unconstrained. Many paleo-observat...
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作者：Lin, Ruitao; Yin, Guosheng
作者单位：University of Hong Kong
摘要：Phase I drug-combination trials are becoming commonplace in oncology. Most of the current dose-finding designs aim to quantify the toxicity probability space using certain prespecified yet complicated models. These models need to characterize not only each individual drug's toxicity profile, but also their interaction effects, which often leads to multi-parameter models. We propose a novel Bayesian adaptive design for drug-combination trials based on a robust dimension-reduction method. We con...
