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作者：Schaubel, Douglas E.; Wolfe, Robert A.; Sima, Camelia S.; Merion, Robert M.
作者单位：University of Michigan System; University of Michigan; Arbor Research Collaborative for Health; Memorial Sloan Kettering Cancer Center; University of Michigan System; University of Michigan
摘要：Few health policy issues in the U.S. are scrutinized as intensely as the distribution of organs for transplantation, with much effort currently underway to examine the efficacy of existing organ allocation algorithms. The design of efficient organ a I location policies depends strongly upon accurate estimates of the Survival benefit of transplantation. Many organ allocation policies order patients on the wait-list based on time-dependent health status measures (internal time-dependent covariat...
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作者：Chib, Siddhartha; Ergashev, Bakhodir
作者单位：Washington University (WUSTL); Federal Reserve System - USA; Federal Reserve Bank - Richmond
摘要：In finance and economics much work has been done on the theoretical modeling and statistical estimation of the yield curve, defined as the relationship between -1/tau logp(t)(tau) and tau, where p(t)(tau) is the time t price of a zero-coupon bond with payoff I at maturity date t + tau. Of considerable current interest are models of the yield curve in which a collection of observed and latent factors determine the market price of factor risks, the stochastic discount factor, and the arbitrage-f...
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作者：El Ghouch, Anouar; Genton, Marc G.
作者单位：University of Geneva; Texas A&M University System; Texas A&M University College Station
摘要：We propose a new approach to conditional quantile function estimation that combines both parametric and nonparametric techniques. At each design point, a global, possibly incorrect, pilot parametric model is locally adjusted through a kernel smoothing fit. The resulting quantile regression estimator behaves like a parametric estimator when the latter is correct and converges to the nonparametric solution as the parametric start deviates from the true underlying model. We give a Bahadur-type re...
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作者：Fokianos, Konstantinos; Rahbek, Anders; Tjostheim, Dag
作者单位：University of Cyprus; University of Copenhagen; CREATES; University of Bergen
摘要：In this article we consider geometric ergodicity and likelihood-based inference for linear and nonlinear Poisson autoregression. In the linear case, the conditional mean is linked linearly to its past values, as well as to the observed values of the Poisson process. This also applies to the conditional variance, making possible interpretation as an integer-valued generalized autoregressive conditional heteroscedasticity process. In a nonlinear conditional Poisson model, the conditional mean is...
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作者：Love, Tanzy; Carriquiry, Alicia
作者单位：Iowa State University; Pontificia Universidad Catolica de Chile
摘要：We analyze data collected in a somatic embryogenesis experiment carried out on Zea mays at Iowa state university. The main objective of the Study was to identify the set of genes in maize that actively participate in embryo development. Embryo tissue was sampled and analyzed at various time periods and under different mediums and light conditions. As is the case in many microarray experiments. the operator scanned each Slide multiple times to find the slide-specific 'optimal' laser and sensor ...
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作者：Hall, Peter; Titterington, D. M.; Xue, Jing-Hao
作者单位：University of Melbourne; University of Glasgow; University of London; University College London
摘要：Conventional distance-based classifiers use standard Euclidean distance, and so can suffer from excessive volatility if vector components have heavy-tailed distributions. This difficulty can be alleviated by replacing the L-2 distance by its L-1 counterpart. For example, the L-1 version of the popular centroid classifier would allocate a new data value to the population to whose centroid it was closest in L-1 terms. However, this approach can lead to inconsistency, because the centroid is defi...
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作者：Wang, Huixia Judy; Wang, Lan
作者单位：North Carolina State University; University of Minnesota System; University of Minnesota Twin Cities
摘要：Censored quantile regression offers a valuable supplement to Cox proportional hazards model for survival analysis. Existing work in the literature often requires stringent assumptions, such as unconditional independence of the survival time and the censoring variable or global linearity at all quantile levels. Moreover, some of the work uses recursive algorithms. making it challenging to derive asymptotic normality. To overcome these drawbacks, we propose a new locally weighted censored quanti...
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作者：Ghosh, Pulak; Tu, Wanzhu
作者单位：University System of Georgia; Georgia State University; Indiana University System; Indiana University Indianapolis; Regenstrief Institute Inc
摘要：Understanding human sexual behaviors is essential for the effective prevention of sexually transmitted infections (STI). Analysis of longitudinally measured sexual behavioral data, however, is often complicated by zero-inflation of event counts, nonlinear time trend, time-varying covariates, and informative dropouts. Ignoring these complicating factors could undermine the validity of the study findings. In this article, we put forth a unified joint modeling structure that accommodates these fe...
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作者：Lopez-Pintado, Sara; Romo, Juan
作者单位：Universidad Pablo de Olavide; Universidad Carlos III de Madrid
摘要：The statistical analysis of functional data is a growing need in many research areas. In particular, a robust methodology is important to study curves, which are the output of many experiments in applied statistics. As a starting point for this robust analysis. we propose, analyze. and apply a new definition of depth for functional based on the graphic observations based presentation of the curves. Given a collection of functions. it establishes the centrality of an observation and provides a ...
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作者：Cook, Richard J.; Lawless, Jerald F.; Lakhal-Chaieb, Lajmi; Lee, Ker-Ai
作者单位：University of Waterloo; Laval University
摘要：In clinical trials featuring recurrent clinical events, the definition and estimation of treatment effects involves a number of interesting issues, especially when loss to follow-up may be event-related and when terminal events such as death preclude the occurrence of further events. This paper discusses a clinical trial of breast cancer patients with bone metastases where the recurrent events are skeletal complications, and where patients may die during the trial. We argue that treatment effe...
