-
作者：Kaziska, David; Srivastava, Anuj
作者单位：Air Force Institute of Technology (AFIT); United States Department of Defense; United States Air Force; US Air Force Research Laboratory; State University System of Florida; Florida State University
摘要：We study the problem of analyzing and classifying human gait by modeling it as a stochastic process on a shape space. We consider gait as a evolution of human silhouettes as seen in video sequences, and focus on their shapes. More specifically, we define a shape space of planar, closed curves and model a human gait as a stochastic process on this space. Due to the periodic nature of human walk, this process is naturally constrained to be cyclostationary, that is, its mean path is assumed to be...
-
作者：Hallin, Marc; Saidi, Abdessamad
作者单位：Universite Libre de Bruxelles; Universite de Montreal
摘要：The problem of testing noncorrelation between two multivariate time series is considered. Assuming that the global process admits a joint vector autoregressive (VAR) representation, noncorrelation between the two component series is equivalent to the hypothesis that all off-diagonal blocks in the matrix coefficients and the innovation covariance of the joint VAR representation are zero. We establish an adequate local asymptotic normality (LAN) property for this VAR model in the vicinity of non...
-
作者：Meiring, Wendy
作者单位：University of California System; University of California Santa Barbara
摘要：A functional data analysis approach is presented to study altitude-dependent patterns of ozone variation in data from a sequence of ozonesonde flights. Ozonesondes are balloon-based instruments that measure ozone as the balloon ascends through the troposphere and lower stratosphere. This article concentrates on variation in the altitude range of 15.5-30.5 kin, in January-July in 1967-1998. Ozonesonde flights originating at a mid-latitude site, Hohenpeissenberg in Germany, are studied. Estimate...
-
作者：Shi, Jianxin; Siegmund, David; Yakir, Benny
作者单位：Stanford University; Hebrew University of Jerusalem
摘要：Importance sampling methods are proposed for estimating the probability that the maximum of a random process exceeds a high threshold, with particular attention to assessing genome-wide significance levels in linkage analysis. The proposed algorithm is applied to computing the conditional significance level, given observed phenotypes, of scan statistics to map quantitative traits in experimental populations and in extended pedigrees of moderate size with partially informative markers. For dete...
-
作者：Wang, Hansheng; Leng, Chenlei
作者单位：Peking University; National University of Singapore
摘要：We propose a method of least squares approximation (LSA) for unified yet simple LASSO estimation. Our general theoretical framework includes ordinary least squares, generalized linear models, quantile regression, and many others as special cases. Specifically, LSA can transfer many different types of LASSO objective functions into their asymptotically equivalent least squares problems. Thereafter, the standard asymptotic theory can be established and the LARS algorithm can be applied. In parti...
-
作者：Morgan, J. P.
作者单位：Virginia Polytechnic Institute & State University
摘要：Optimal incomplete block designs are pursued through the E criterion of minimizing maximal variance. Methodology is developed for design choice based on graphs and an extensive catalog of downloadable designs is compiled. Along with the general methodology, a near complete solution for E-optimal block designs is provided for up to 15 treatments. E optimality is revealed to be a flexible criterion that, depending on the application, can offer many choices for good designs.
-
作者：Altman, Rachel MacKay
作者单位：Simon Fraser University
摘要：Hidden Markov models (HMMs) are a useful tool for capturing the behavior of overdispersed, autocorrelated data. These models have been applied to many different problems, including speech recognition, precipitation modeling, and gene finding and profiling. Typically, HMMs are applied to individual stochastic processes; HMMs for simultaneously modeling multiple processes-as in the longitudinal data setting-have not been widely studied. In this article I present a new class of models, mixed HMMs...
-
作者：Cooley, Daniel; Nychka, Douglas; Naveau, Philippe
作者单位：Colorado State University System; Colorado State University Fort Collins; National Center Atmospheric Research (NCAR) - USA; National Center Atmospheric Research (NCAR) - USA; Universite Paris Saclay; Centre National de la Recherche Scientifique (CNRS); Universite Paris Cite; University of Colorado System; University of Colorado Boulder
摘要：Quantification of precipitation extremes is important for flood planning purposes, and a common measure of extreme events is the r-year return level. We present a method for producing maps of precipitation return levels and uncertainty measures and apply it to a region in Colorado. Separate hierarchical models are constructed for the intensity and the frequency of extreme precipitation events. For intensity, we model daily precipitation above a high threshold at 56 weather stations with the ge...
-
作者：Reich, Brian J.; Hodges, James S.; Carlin, Bradley P.
作者单位：University of Minnesota System; University of Minnesota Twin Cities
摘要：Attachment loss, the extent of a tooth's root (in millimeters) that is no longer attached to surrounding bone by periodontal ligament, is often used to measure the current state of a patient's periodontal disease and monitor disease progression. Attachment loss data can be analyzed using a conditionally autoregressive (CAR) prior distribution that smooths fitted values toward neighboring values. However, it may be desirable to have more than one class of neighbor relation in the spatial struct...
-
作者：Fan, Jianqing; Hall, Peter; Yao, Qiwei
作者单位：Princeton University; Chinese Academy of Sciences; Academy of Mathematics & System Sciences, CAS; University of Melbourne
摘要：In the analysis of microarray data, and in some other contemporary statistical problems, it is not uncommon to apply hypothesis tests in a highly simultaneous way. The number, N say, of tests used can be much larger than the sample sizes, n, to which the tests are applied, yet we wish to calibrate the tests so that the overall level of the simultaneous test is accurate. Often the sampling distribution is quite different for each test, so there may not be an opportunity to combine data across s...
