-
作者：Einmahl, John H. J.; Magnus, Jan R.
作者单位：Tilburg University; Tilburg University
摘要：We are interested in two questions on extremes relating to world records in athletics. The first question is: What is the ultimate world record in a specific athletic event (such as the 100-m race for men or the high jump for women), given today's state of the art? Our second question is: How good is a current athletic world record? An answer to the second question also enables us to compare the quality of world records in different athletic events. We consider these questions for each of 28 e...
-
作者：Caffo, Brian S.; Crainiceanu, Ciprian M.; Deng, Lijuan; Hendrix, Craig W.
作者单位：Johns Hopkins University; Johns Hopkins Bloomberg School of Public Health; Boston Scientific; Johns Hopkins University; Johns Hopkins Medicine; Johns Hopkins University; Johns Hopkins Medicine
摘要：In this article we are concerned with functional imaging of the colon to assess the kinetics of microbicide lubricants. The overarching goal IS to understand the distribution of the lubricants in the colon. Such information is crucial for understanding the potential impact of microbicides on human immunodeficiency virus transmission. The experiment was conducted by imaging a radiolabeled lubricant distributed in the subject's colon. The tracer imaging was conducted via single-photon emission c...
-
作者：Doksum, Kjell; Tang, Shijie; Tsui, Kam-Wah
作者单位：University of Wisconsin System; University of Wisconsin Madison; Bristol-Myers Squibb
摘要：We consider regression experiments involving a response variable Y and a large number of predictor variables X-1,...,X-d, many of which may be irrelevant for the prediction of Y and thus must be removed before Y can be predicted from the X's. We consider two procedures that select variables by using importance scores that measure the strength of the relationship between predictor variables and a response and keep those variables whose importance scores exceed a threshold. In the first of these...
-
作者：Shadish, William R.; Clark, M. H.; Steiner, Peter M.
作者单位：University of California System; University of California Merced; Southern Illinois University System; Southern Illinois University
-
作者：Chiou, Jeng-Min; Li, Pai-Ling
作者单位：Tamkang University
摘要：A correlation-based functional clustering method is proposed for grouping curves with similar shapes. A correlation between two random functions defined through the functional inner product is used as a similarity measure. Curves with similar shapes are embedded in the cluster subspace spanned by a a mean shape function and eigenfunctions of the covariance kernel. The cluster membership prediction for each curve attempts to maximize the functional correlation between the observed and predicted...
-
作者：O'Malley, A. James; Zaslavsky, Alan M.
作者单位：Harvard University; Harvard Medical School
摘要：Health care quality surveys in the United States are administered to individual respondents (i.e.. hospital patients, health plan members) to evaluate the performance of health care organizations (i.e., hospitals, health plans). which thus Constitute estimation domains. For better understanding and more parsimonious reporting of dimensions of quality, we analyze relationships among., quality Measures at the domain level. Rather than specifying a full parametric model for the observed responses...
-
作者：Dunson, David B.; Herring, Amy H.; Siega-Riz, Anna Maria
作者单位：Duke University; University of North Carolina; University of North Carolina Chapel Hill; University of North Carolina; University of North Carolina Chapel Hill; University of North Carolina; University of North Carolina Chapel Hill
摘要：In epidemiology, it often is of interest to assess how individuals with different trajectories over time in an environmental exposure or biomarker differ with respect to a continuous response. For ease in interpretation and presentation of results. epidemiologists typically categorize predictors before analysis. To extend this approach to time-varying predictors, individuals can be clustered by then predictor trajectory, with the cluster index included as a predictor in a regression model for ...
-
作者：Gao, Jiti; Gijbels, Irene
作者单位：University of Adelaide; Universite Catholique Louvain
摘要：We propose a sound approach to bandwidth selection in nonparametric kernel testing. The main idea is to find an Edgeworth expansion of the asymptotic distribution of the test concerned Due to the involvement of a kernel bandwidth in the leading term of the Edgeworth expansion. we dire able to establish closed-form expressions to explicitly represent the leading terms of both the size and power functions and then determine how the bandwidth should be chosen according to certain requirements for...
-
作者：Shepherd, Bryan E.; Redman, Mary W.; Ankerst, Donna R.
作者单位：Vanderbilt University; Technical University of Munich
摘要：In 2003 Thompson and colleagues reported that daily use of finasteride reduced the prevalence of prostate cancer by 25% compared to placebo. These results were based oil the double-blind randomized Prostate Cancer Prevention Trial (PCPT), which followed 18.882 men with no prior Or Current indications of prostate cancer annually for 7 years. Enthusiasm for the risk reduction afforded by the chemopreventative agent and adoption Of its use in clinical practice. however. was severely dampened by (...
-
作者：Kim, Yongdai; Choi, Hosik; Oh, Hee-Seok
作者单位：Seoul National University (SNU); Hoseo University
摘要：The smoothly clipped absolute deviation (SCAD) estimator, proposed by Fan and Li, has many desirable properties, including continuity, sparsity, and unbiasedness. The SCAD estimator also has the (asymptotically) oracle property when the dimension of covariates is fixed or diverges more slowly than the sample size. In this article we study the SCAD estimator in high-dimensional settings where the dimension of covariates can be much larger than the sample size. First, we develop and efficient op...
