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作者：Reich, Brian J.; Shaby, Benjamin A.
作者单位：North Carolina State University; University of California System; University of California Berkeley
摘要：Extreme environmental phenomena such as major precipitation events manifestly exhibit spatial dependence. Max-stable processes are a class of asymptotically-justified models that are capable of representing spatial dependence among extreme values. While these models satisfy modeling requirements, they are limited in their utility because their corresponding joint likelihoods are unknown for more than a trivial number of spatial locations, preventing, in particular, Bayesian analyses. In this p...
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作者：Baggaley, Andrew W.; Boys, Richard J.; Golightly, Andrew; Sarson, Graeme R.; Shukurov, Anvar
作者单位：Newcastle University - UK
摘要：We consider parameter estimation for the spread of the Neolithic incipient farming across Europe using radiocarbon dates. We model the arrival time of farming at radiocarbon-dated, early Neolithic sites by a numerical solution to an advancing wavefront. We allow for (technical) uncertainty in the radiocarbon data, lack-of-fit of the deterministic model and use a Gaussian process to smooth spatial deviations from the model. Inference for the parameters in the wavefront model is complicated by t...
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作者：Liu, Hai; Tu, Wanzhu
作者单位：Indiana University System; Indiana University Bloomington
摘要：This research examines the simultaneous influences of height and weight on longitudinally measured systolic and diastolic blood pressure in children. Previous studies have shown that both height and weight are positively associated with blood pressure. In children, however, the concurrent increases of height and weight have made it all but impossible to discern the effect of height from that of weight. To better understand these influences, we propose to examine the joint effect of height and ...
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作者：Cooley, Daniel; Davis, Richard A.; Naveau, Philippe
作者单位：Colorado State University System; Colorado State University Fort Collins; Columbia University; Centre National de la Recherche Scientifique (CNRS); Universite Paris Saclay
摘要：Phenomena such as air pollution levels are of greatest interest when observations are large, but standard prediction methods are not specifically designed for large observations. We propose a method, rooted in extreme value theory, which approximates the conditional distribution of an unobserved component of a random vector given large observed values. Specifically, for Z = (Z(1), ... , Z(d))(T) and Z(-d) = (Z(1), ... , Z(d-1))(T), the method approximates the conditional distribution of [Z(d) ...
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作者：Aston, John A. D.; Kirch, Claudia
作者单位：University of Warwick; Helmholtz Association; Karlsruhe Institute of Technology
摘要：Functionalmagnetic resonance imaging (fMRI) is now a well-established technique for studying the brain. However, in many situations, such as when data are acquired in a resting state, it is difficult to know whether the data are truly stationary or if level shifts have occurred. To this end, change-point detection in sequences of functional data is examined where the functional observations are dependent and where the distributions of change-points from multiple subjects are required. Of parti...
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作者：Aksakalli, Vural; Ceyhan, Elvan
作者单位：Istanbul Sehir University; Koc University
摘要：We introduce the optimal obstacle placement with disambiguations problem wherein the goal is to place true obstacles in an environment cluttered with false obstacles so as to maximize the total traversal length of a navigating agent (NAVA). Prior to the traversal, the NAVA is given location information and probabilistic estimates of each disk-shaped hindrance (hereinafter referred to as disk) being a true obstacle. The NAVA can disambiguate a disk's status only when situated on its boundary. T...
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作者：Tilahun, Gelila; Feuerverger, Andrey; Gervers, Michael
作者单位：University of Toronto; University of Toronto
摘要：Deeds, or charters, dealing with property rights, provide a continuous documentation which can be used by historians to study the evolution of social, economic and political changes. This study is concerned with charters (written in Latin) dating from the tenth through early fourteenth centuries in England. Of these, at least one million were left undated, largely due to administrative changes introduced by William the Conqueror in 1066. Correctly dating such charters is of vital importance in...
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作者：Illian, Janine B.; Sorbye, Sigrunn H.; Rue, Havard
作者单位：University of St Andrews; UiT The Arctic University of Tromso; Norwegian University of Science & Technology (NTNU)
摘要：This paper develops methodology that provides a toolbox for routinely fitting complex models to realistic spatial point pattern data. We consider models that are based on log-Gaussian Cox processes and include local interaction in these by considering constructed covariates. This enables us to use integrated nested Laplace approximation and to considerably speed up the inferential task. In addition, methods for model comparison and model assessment facilitate the modelling process. The perform...
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作者：Sigrist, Fabio; Kuensch, Hans R.; Stahel, Werner A.
作者单位：Swiss Federal Institutes of Technology Domain; ETH Zurich
摘要：Precipitation is a complex physical process that varies in space and time. Predictions and interpolations at unobserved times and/or locations help to solve important problems in many areas. In this paper, we present a hierarchical Bayesian model for spatio-temporal data and apply it to obtain short term predictions of rainfall. The model incorporates physical knowledge about the underlying processes that determine rainfall, such as advection, diffusion and convection. It is based on a tempora...
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作者：Ba, Shan; Joseph, V. Roshan
作者单位：University System of Georgia; Georgia Institute of Technology
摘要：A new type of nonstationary Gaussian process model is developed for approximating computationally expensive functions. The new model is a composite of two Gaussian processes, where the first one captures the smooth global trend and the second one models local details. The new predictor also incorporates a flexible variance model, which makes it more capable of approximating surfaces with varying volatility. Compared to the commonly used stationary Gaussian process model, the new predictor is n...
