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作者：Di Marzio, Marco; Panzera, Agnese; Taylor, Charles C.
作者单位：G d'Annunzio University of Chieti-Pescara; University of Florence; University of Leeds
摘要：We develop nonparametric smoothing for regression when both the predictor and the response variables are defined on a sphere of whatever dimension. A local polynomial fitting approach is pursued, which retains all the advantages in terms of rate optimality, interpretability, and ease of implementation widely observed in the standard setting. Our estimates have a multi-output nature, meaning that each coordinate is separately estimated, within a scheme of a regression with a linear response. Th...
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作者：Cai, Zongwu; Wang, Xian
作者单位：University of Kansas; Xiamen University; Bank of America Corporation
摘要：A fundamental issue of applying a copula method in applications is how to choose an appropriate copula function for a given problem. In this article we address this issue by proposing a new copula selection approach via penalized likelihood plus a shrinkage operator. The proposed method selects an appropriate copula function and estimates the related parameters simultaneously. We establish the asymptotic properties of the proposed penalized likelihood estimator, including the rate of convergen...
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作者：Chen, L.; Dou, W. W.; Qiao, Z.
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作者：Jin, Ick Hoon; Liu, Suyu; Thall, Peter F.; Yuan, Ying
作者单位：University of Texas System; UTMD Anderson Cancer Center
摘要：A practical impediment in adaptive clinical trials is that outcomes must be observed soon enough to apply decision rules to choose treatments for new patients. For example, if outcomes take up to six weeks to evaluate and the accrual rate is one patient per week, on average three new patients will be accrued while waiting to evaluate the outcomes of the previous three patients. The question is how to treat the new patients. This logistical problem persists throughout the trial. Various ad hoc ...
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作者：Xiao, Yongling; Abrahamowicz, Michal; Moodie, Erica E. M.; Weber, Rainer; Young, James
作者单位：McGill University; University of Zurich; University Zurich Hospital; University of Basel; Swiss School of Public Health (SSPH+)
摘要：The association between antiretroviral treatment and cardiovascular disease (CVD) risk in HIV-positive persons has been the subject of much debate since the Data collection on Adverse events of Anti-HIV Drugs (D: A: D) study reported that recent use of two antiretroviral drugs, abacavir (ABC) and didanosine (DDI), was associated with increased risk. We focus on the potential impact of DDI use, as this drug has not been as studied intensively as ABC. We propose a flexible marginal structural Co...
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作者：Lu, Xiaosun; Marron, J. S.; Haaland, Perry
作者单位：University of North Carolina; University of North Carolina Chapel Hill
摘要：This article discusses a study of cell images in cell culture biology from an object-oriented point of view. The motivation of this research is to develop a statistical approach to cell image analysis that better supports the automated development of stem cell growth media. A major hurdle in this process is the need for human expertise, based on studying cells under the microscope, to make decisions about the next step of the cell culture process. We aim to use digital imaging technology coupl...
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作者：Minas, Giorgos; Aston, John A. D.; Stallard, Nigel
作者单位：University of Warwick; University of Warwick
摘要：We present a methodology for dealing with recent challenges in testing global hypotheses using multivariate observations. The proposed tests target situations, often arising in emerging applications of neuroimaging, where the sample size n is relatively small compared with the observations' dimension K. We employ adaptive designs allowing for sequential modifications of the test statistics adapting to accumulated data. The adaptations are optimal in the sense of maximizing the predictive power...
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作者：Percival, Daniel M.; Percival, Donald B.; Denbo, Donald W.; Gica, Edison; Huang, Paul Y.; Mofjeld, Harold O.; Spillane, Michael C.
作者单位：Alphabet Inc.; Google Incorporated; University of Washington; University of Washington Seattle; University of Washington; University of Washington Seattle; University of Washington; University of Washington Seattle; National Oceanic Atmospheric Admin (NOAA) - USA; National Oceanic Atmospheric Admin (NOAA) - USA
摘要：In response to hazards posed by earthquake-induced tsunamis, the National Oceanographic and Atmospheric Administration developed a system for issuing timely warnings to coastal communities. This system, in part, involves matching data collected in real time from deep-ocean buoys to a database of precomputed geophysical models, each associated with a geographical location. Currently, trained operators must handpick models from the database using the epicenter of the earthquake as guidance, whic...
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作者：Ayra, Eduardo S.; Rios Insua, David; Cano, Javier
作者单位：Universidad Rey Juan Carlos
摘要：According to the International Air Transport Association, the industry fuel bill accounts for more than 25% of the annual airline operating costs. In times of severe economic constraints and increasing fuel costs, air carriers are looking for ways to reduce costs and improve fuel efficiency without putting flight safety into jeopardy. In particular, this is inducing discussions on how much additional fuel to put in a planned route to avoid diverting to an alternate airport due to Air Traffic F...
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作者：Liu, Xu; Jiang, Hongmei; Zhou, Yong
作者单位：Northwestern University; Chinese Academy of Sciences; Academy of Mathematics & System Sciences, CAS; Shanghai University of Finance & Economics
摘要：In this article, we develop a varying-coefficient density-ratio model for case-control studies. The case and control samples come from two different distributions. Under the model assumption, the ratio of the two densities is related to the linear combination of covariates with varying coefficients through a known function. A special case is the exponential tilt model where the log ratio of the two densities is a linear function of covariates. We propose a local empirical likelihood (EL) appro...
