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作者：Bhaumik, Dulal K.; Amatya, Anup; Normand, Sharon-Lise T.; Greenhouse, Joel; Kaizar, Eloise; Neelon, Brian; Gibbons, Robert D.
作者单位：University of Illinois System; University of Illinois Chicago; University of Illinois Chicago Hospital; New Mexico State University; Harvard University; Harvard Medical School; Carnegie Mellon University; University System of Ohio; Ohio State University; Duke University; University of Chicago; University of Chicago; University of Chicago
摘要：We examine the use of fixed-effects and random-effects moment-based meta-analytic methods for analysis of binary adverse-event data. Special attention is paid to the case of rare adverse events that are commonly encountered in routine practice. We study estimation of model parameters and between-study heterogeneity. In addition, we examine traditional approaches to hypothesis testing of the average treatment effect and detection of the heterogeneity of treatment effect across studies. We deriv...
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作者：Maitra, Ranjan; Melnykov, Volodymyr; Lahiri, Soumendra N.
作者单位：Iowa State University; Iowa State University; North Dakota State University Fargo; Texas A&M University System; Texas A&M University College Station
摘要：This article proposes a bootstrap approach for assessing significance in the clustering of multidimensional datasets. The procedure compares two models and declares the more complicated model a better candidate if there is significant evidence in its favor. The performance of the procedure is illustrated on two well-known classification datasets and comprehensively evaluated in terms of its ability to estimate the number of components via extensive simulation studies, with excellent results. T...
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作者：Han, Summer S.; Rosenberg, Philip S.; Chatterjee, Nilanjan
作者单位：National Institutes of Health (NIH) - USA; NIH National Cancer Institute (NCI); NIH National Cancer Institute- Division of Cancer Epidemiology & Genetics
摘要：Recent genome-wide association studies (GWASs) designed to detect the main effects of genetic markers have had considerable success with many findings validated by replication studies. However, relatively few findings of gene-gene or gene-environment interactions have been successfully reproduced. Besides the main issues associated with insufficient sample size in current studies, a complication is that interactions that rank high based on p-values often correspond to extreme forms of joint ef...
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作者：Carroll, Raymond; Delaigle, Aurore; Hall, Peter
作者单位：Texas A&M University System; Texas A&M University College Station; University of Melbourne
摘要：In the present study, we consider the problem of classifying spatial data distorted by a linear transformation or convolution and contaminated by additive random noise. In this setting, we show that classifier performance can be improved if we carefully invert the data before the classifier is applied. However, the inverse transformation is not constructed so as to recover the original signal, and in fact, we show that taking the latter approach is generally inadvisable. We introduce a fully d...
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作者：Danilov, Mike; Yohai, Victor J.; Zamar, Ruben H.
作者单位：Alphabet Inc.; Google Incorporated; University of Buenos Aires; University of British Columbia
摘要：Two main issues regarding data quality are data contamination (outliers) and data completion (missing data). These two problems have attracted much attention and research but surprisingly, they are seldom considered together. Popular robust methods such as S-estimators of multivariate location and scatter offer protection against outliers but cannot deal with missing data, except for the obviously inefficient approach of deleting all incomplete cases. We generalize the definition of S-estimato...
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作者：Kang, Hakmook; Ombao, Hernando; Linkletter, Crystal; Long, Nicole; Badre, David
作者单位：Vanderbilt University; University of California System; University of California Irvine; Brown University; Brown University
摘要：The goal of this article is to model cognitive control related activation among predefined regions of interest (ROIs) of the human brain while properly adjusting for the underlying spatio-temporal correlations. Standard approaches to fMRI analysis do not simultaneously take into account both the spatial and temporal correlations that are prevalent in fMRI data. This is primarily due to the computational complexity of estimating the spatio-temporal covariance matrix. More specifically, they do ...
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作者：Sun, Wenguang; McLain, Alexander C.
作者单位：University of Southern California; National Institutes of Health (NIH) - USA; NIH Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD)
摘要：In large-scale studies, the true effect sizes often range continuously from zero to small to large, and are observed with heteroscedastic errors. In practical situations where the failure to reject small deviations from the null is inconsequential, specifying an indifference region (or forming composite null hypotheses) can greatly reduce the number of unimportant discoveries in multiple testing. The heteroscedasticity issue poses new challenges for multiple testing with composite nulls. In pa...
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作者：Zubizarreta, Jose R.
作者单位：University of Pennsylvania
摘要：This article presents a new method for optimal matching in observational studies based on mixed integer programming. Unlike widely used matching methods based on network algorithms, which attempt to achieve covariate balance by minimizing the total sum of distances between treated units and matched controls, this new method achieves covariate balance directly, either by minimizing both the total sum of distances and a weighted sum of specific measures of covariate imbalance, or by minimizing t...
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作者：Jin, Jiashun
作者单位：Carnegie Mellon University
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作者：Luati, Alessandra; Proietti, Tommaso; Reale, Marco
作者单位：University of Bologna; University of Sydney; University of Rome Tor Vergata; University of Canterbury
摘要：The variance profile is defined as the power mean of the spectral density function of a stationary stochastic process. It is a continuous and nondecreasing function of the power parameter, p, which returns the minimum of the spectrum (p -> infinity), the interpolation error variance (harmonic mean, p = -1), the prediction error variance (geometric mean, p = 0), the unconditional variance (arithmetic mean, p = 1), and the maximum of the spectrum (p -> infinity). The variance profile provides a ...
