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作者：Bartlett, PL; Jordan, MI; McAuliffe, JD
作者单位：University of California System; University of California Berkeley; University of California System; University of California Berkeley
摘要：Many of the classification algorithms developed in the machine learning literature, including the support vector machine and boosting, can be viewed as minimum contrast methods that minimize a convex surrogate of the 0-1 loss function. The convexity makes these algorithms computationally efficient. The use of a surrogate, however, has statistical consequences that must be balanced against the computational virtues of convexity. To study these issues, we provide a general quantitative relations...
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作者：Nan, B; Lin, XH; Lisabeth, LD; Harlow, SD
作者单位：University of Michigan System; University of Michigan; Harvard University; Harvard T.H. Chan School of Public Health; University of Michigan System; University of Michigan; University of Michigan System; University of Michigan
摘要：A question of significant interest in female reproductive aging is to identify bleeding criteria for menopausal transition. Although various bleeding criteria, or markers, have been proposed for menopausal transition, their validity has not been adequately examined. The Tremin Trust data were collected from a long-term cohort study that followed a group of women throughout their whole reproductive life. Such data provide a unique opportunity for evaluating the utility of a bleeding criterion-b...
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作者：Lin, DY; Zeng, D
作者单位：University of North Carolina; University of North Carolina Chapel Hill
摘要：A haplotype is a specific sequence of nucleotides on a single chromosome. The population associations between haplotypes and disease phenotypes provide critical information about the genetic basis of complex human diseases. Standard genotyping techniques cannot distinguish the two homologous chromosomes of an individual, so only the unphased genotype (i.e., the combination of the two homologous haplotypes) is directly observable. Statistical inference about haplotype-phenotype associations bas...
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作者：Morales, KH; Ibrahim, JG; Chen, CJ; Ryan, LM
作者单位：University of Pennsylvania; University of Pennsylvania; University of North Carolina; University of North Carolina Chapel Hill; National Taiwan University; Harvard University; Harvard T.H. Chan School of Public Health
摘要：An important component of quantitative risk assessment involves characterizing the dose-response relationship between an environmental exposure and adverse health outcome and then computing a benchmark dose, or the exposure level that yields a suitably low risk. This task is often complicated by model choice considerations, because risk estimates depend on the model parameters. We pro pose using Bayesian methods to address the problem of model selection and derive a model-averaged version of t...
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作者：Satten, GA; Allen, AS; Epstein, MR
作者单位：Centers for Disease Control & Prevention - USA; Duke University; Duke University; Emory University
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作者：Su, ZH; Yang, SS
作者单位：Harvard University; Harvard T.H. Chan School of Public Health; Kansas State University
摘要：A class of three tests-overall lack-of-fit test, between-cluster lack-of-fit test. and within-cluster lack-of-fit test-are proposed for testing the lack of fit of a linear regression model applied to experiments without replicates. The power of the proposed tests is significantly higher than those of the known tests under the situations considered here. The proposed tests are capable of detecting which type of lack of fit is dominant when both between-cluster and within-cluster lack of fit are...
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作者：Casella, G; Moreno, E
作者单位：State University System of Florida; University of Florida; University of Granada
摘要：A novel fully automatic Bayesian procedure for variable selection in normal regression models is proposed. The procedure uses the posterior probabilities of the models to drive a stochastic search. The posterior probabilities are computed using intrinsic priors, which can be considered default priors for model selection problems; that is, they are derived from the model structure and are free from tuning parameters. Thus they can be seen as objective priors for variable selection. The stochast...
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作者：Hitchcock, DB; Casella, G; Booth, JG
作者单位：University of South Carolina System; University of South Carolina Columbia; State University System of Florida; University of Florida; Cornell University
摘要：We examine the effect of presmoothing functional data oil estimating the dissimilarities among objects in a dataset, with applications to cluster analysis and other distance methods, such as multidimensional scaling and statistical matching. We prove that a shrinkage method of smoothing results in a better estimator of the dissimilarities among a set of noisy curves. For a model with independent noise structure, the smoothed-data dissimilarity estimator dominates the observed-data estimator. F...
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作者：De Santis, F
作者单位：Sapienza University Rome
摘要：This article considers a robust Bayesian approach to the sample size determination problem. We focus on global Bayesian robustness that studies lower bound (L-n), upper bound (U-n), and range (R-n) of posterior quantities of interest. obtained as the prior varies in a class of distributions. Specifically, we are interested in the selection of an appropriate sample size that gives guarantees to the researcher of observing a small value of the range and, depending on the problems, either a suffi...
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作者：Heard, NA; Holmes, CC; Stephens, DA
作者单位：Imperial College London; University of Oxford; MRC Harwell
摘要：Malaria represents one of the major worldwide challenges to public health. A recent breakthrough in the study of the disease follows the annotation of the genome of the malaria parasite Plasmodium falciparum and the mosquito vector (an organism that spreads an infectious disease) Anopheles. Of particular interest is the molecular biology underlying the immune response system of Anopheles, which actively fights against Plasmodium infection. This article reports a statistical analysis of gene ex...
