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作者：Rivest, Louis-Paul; Baillargeon, Sophie; Pierrynowski, Michael
作者单位：Laval University; McMaster University
摘要：This article is motivated by the estimation of the direction of the two rotation axes of the ankle. These axes carry information on individual ankles: they are useful in the construction of biomechanical models and the treatment of orthopedic problems. In biomechanics, the rotation axes of the ankle often are estimated using optimization techniques. This work investigates a statistical model for carrying out the estimation. The data set for analysis is a time-ordered sequence of 3x3 rotation m...
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作者：Yin, Guosheng; Li, Hui; Zeng, Donglin
作者单位：University of Texas System; UTMD Anderson Cancer Center; Beijing Normal University; University of North Carolina; University of North Carolina Chapel Hill
摘要：To explore the nonlinear interactions between some covariates and an exposure variable, we propose the partially linear additive hazards model for survival data. In a semiparametric setting, we construct a local pseudoscore function to estimate the varying and constant coefficients and establish the asymptotic normality of the proposed estimators. Moreover, we develop the weak convergence property for the local estimator of the baseline cumulative hazard function. We conduct simulation studies...
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作者：Li, Bing; Wen, Songqiao; Zhu, Lixing
作者单位：Pennsylvania Commonwealth System of Higher Education (PCSHE); Pennsylvania State University; Pennsylvania State University - University Park; Hong Kong Baptist University; Hong Kong Baptist University
摘要：Consider the dimension reduction problem where both the response and the predictor are vectors. Existing estimators of this problem take one of the following routes: (1) targeting the part of the dimension reduction space that is related to the conditional mean (or moments) of the response space directly by multivariate slicing. However, the first two approaches do not fully recover the dimension reduction space, and the third is hampered by the fact that the accuracy of estimators based on mu...
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作者：Guan, Yongtao
作者单位：Yale University
摘要：A common nonparametric approach to estimate the intensity function of an inhomogeneous spatial point process is through kernel smoothing. When conducting the smoothing, one typically uses events only in a local set around the point of interest. But the resulting estimator often is inconsistent, because the number of events in a fixed set is of order 1 for spatial point processes. In this article we propose a new covariance-based kernel smoothing method to estimate the intensity function. Our m...
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作者：Wang, Shanshan; Jank, Wolfgang; Shmueli, Galit; Smith, Paul
作者单位：University System of Maryland; University of Maryland College Park
摘要：Empirical research of online auctions has grown dramatically in recent years. Studies using publicly available bid data from such wedsites as eBay.com have found many divergences of bidding behavior and auction outcomes compared with ordinary offline auctions and auction theory. Among the main differences between online and offline auctions are the former's longer duration, anonymity of bidders and sellers, and low barriers of entry. All of these factors lead to dynamics in the bid arrival and...
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作者：Kneip, Alois; Ramsay, James O.
作者单位：University of Bonn; University of Bonn
摘要：A registration method can be defined as a process of aligning features of a sample of curves by monotone transformations of their domain. The aligned curves exhibit only amplitude variation, and the domain transformations, called warping functions, capture the phase variation in the original curves. In this article we precisely define a new type of registration process, in which the warping functions optimize the fit of a principal components decomposition to the aligned curves. The principal ...
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作者：Iaci, Ross; Yin, Xiangrong; Sriram, T. N.; Klingenberg, Christian Peter
作者单位：William & Mary; University System of Georgia; University of Georgia; University of Manchester
摘要：In this article we propose a new general index that measures relationships between multiple sets of random vectors. This index is based on Kullback-Leibler (KL) information, which measures linear or nonlinear dependence between multiple sets using joint and marginal densities of affine transformations of the random vectors. Estimates of the matrixes are obtained by maximizing the KL information and are shown to be consistent. The motivation for introducing such an index comes from morphologica...
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作者：Bae, Kyounghwa; Mallick, Bani K.; Elsik, Christine G.
作者单位：American College of Radiology; Texas A&M University System; Texas A&M University College Station; Georgetown University
摘要：Proteins have tow types of regions: linker regions that connect active domains and nonlinker regions, which include domains and terminal residues. It is important to try to distinguish these regions using information in the sequence of amino acids that, when folded, form the protein. In this article we develop a nonstationary hidden Markov model to infer region boundaries. The approach is based on a latent variable defined on the sequence, this variable is a continuous index of the region type...
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作者：Corkrey, Ross; Brooks, Steve; Lusseau, David; Parsons, Kim; Durban, John W.; Hammond, Philip S.; Thompson, Paul M.
作者单位：University of Cambridge; National Oceanic Atmospheric Admin (NOAA) - USA; University of St Andrews; University of Aberdeen
摘要：We develop a Bayesian capture-recapture model that provides estimates of abundance as well as time-varying and heterogeneous survival and capture probability distributions. The model uses a state-space approach by incorporating an underlying population model and an observation model, and here is applied to photo-identification data to estimate trends in the abundance and survival of a population of bottlenose dolphins (Tursiops truncatus) in northeast Scotland. Novel features fo the mdoel incl...
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作者：van Wieringen, Wessel N.; van de Wiel, Mark A.; van der Vaart, Aad W.
作者单位：Vrije Universiteit Amsterdam; Vrije Universiteit Amsterdam; Amsterdam University Medical Center
摘要：Even in a single-tissue type cancer is often a collection of different diseases, each with its own genetic mechanism. Consequently, a gene may be expressed in some but not all of the tissues in a sample. Differentially expressed genes are commonly detected by methods that test for a shift in location that ignore the possibility of heterogeneous expression. This article proposes a two-sample test statistic designed to detect shifts that occur in only a part of the sample (partial shifts). The s...
