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作者：Hsu, Li; Gorfine, Malka; Zucker, David
作者单位：Fred Hutchinson Cancer Center; Tel Aviv University; Hebrew University of Jerusalem
摘要：The population-based case-control study design has been widely used for studying the etiology of chronic diseases. It is well established that the Cox proportional hazards model can be adapted to the case-control study and hazard ratios can be estimated by (conditional) logistic regression model with time as either a matched set or a covariate. However, the baseline hazard function, a critical component in absolute risk assessment, is unidentifiable, because the ratio of cases and controls is ...
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作者：Ma, Li; Soriano, Jacopo
作者单位：Duke University; Alphabet Inc.; Google Incorporated
摘要：We introduce a wavelet-domain method for functional analysis of variance (fANOVA). It is based on a Bayesian hierarchical model that employs a graphical hyperprior in the form of a Markov grove (MG)-that is, a collection of Markov trees-for linking the presence/absence of factor effects at all location-scale combinations, there-by incorporating the natural clustering of factor effects in the wavelet-domain across locations and scales. Inference under the model enjoys both analytical simplicity...
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作者：Arias-Castro, Ery; Castro, Rui M.; Tanczos, Ervin; Wang, Meng
作者单位：University of California System; University of California San Diego; Eindhoven University of Technology; Stanford University
摘要：The scan statistic is by far the most popular method for anomaly detection, being popular in syndromic surveillance, signal and image processing, and target detection based on sensor networks, among other applications. The use of the scan statistics in such settings yields a hypothesis testing procedure, where the null hypothesis corresponds to the absence of anomalous behavior. If the null distribution is known, then calibration of a scan-based test is relatively easy, as it can be done by Mo...
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作者：Davidov, Ori; Jelsema, Casey M.; Peddada, Shyamal
作者单位：University of Haifa; West Virginia University; National Institutes of Health (NIH) - USA; NIH National Institute of Environmental Health Sciences (NIEHS)
摘要：There are many applications in which a statistic follows, at least asymptotically, a normal distribution with a singular or nearly singular variance matrix. A classic example occurs in linear regression models under multicollinearity but there are many more such examples. There is well-developed theory for testing linear equality constraints when the alternative is two-sided and the variance matrix is either singular or nonsingular. In recent years, there is considerable, and growing, interest...
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作者：Ganong, Peter; Jaeger, Simon
作者单位：National Bureau of Economic Research; University of Chicago; Massachusetts Institute of Technology (MIT); University of Bonn; IZA Institute Labor Economics; Leibniz Association; Ifo Institut
摘要：The regression kink (RK) design is an increasingly popular empirical method for estimating causal effects of policies, such as the effect of unemployment benefits on unemployment duration. Using simulation studies based on data from existing RK designs, we empirically document that the statistical significance of RK estimators based on conventional standard errors can be spurious. In the simulations, false positives arise as a consequence of nonlinearities in the underlying relationship betwee...
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作者：Zhang, Chong; Wang, Wenbo; Qiao, Xingye
作者单位：University of Waterloo; State University of New York (SUNY) System; Binghamton University, SUNY
摘要：In many real applications of statistical learning, a decision made from misclassification can be too costly to afford; in this case, a reject option, which defers the decision until further investigation is conducted, is often preferred. In recent years, there has been much development for binary classification with a reject option. Yet, little progress has been made for the multicategory case. In this article, we propose margin-based multicategory classification methods with a reject option. ...
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作者：Weinstein, Asaf; Ma, Zhuang; Brown, Lawrence D.; Zhang, Cun-Hui
作者单位：Stanford University; University of Pennsylvania; University of Pennsylvania; Rutgers University System; Rutgers University New Brunswick
摘要：The problem of estimating the mean of a normal vector with known but unequal variances introduces substantial difficulties that impair the adequacy of traditional empirical Bayes estimators. By taking a different approach that treats the known variances as part of the random observations, we restore symmetry and thus the effectiveness of such methods. We suggest a group-linear empirical Bayes estimator, which collects observations with similar variances and applies a spherically symmetric esti...
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作者：Happ, Clara; Greven, Sonja
作者单位：University of Munich
摘要：Existing approaches for multivariate functional principal component analysis are restricted to data on the same one-dimensional interval. The presented approach focuses on multivariate functional data on different domains that may differ in dimension, such as functions and images. The theoretical basis for multivariate functional principal component analysis is given in terms of a Karhunen-Loeve Theorem. For the practically relevant case of a finite Karhunen-Loeve representation, a relationshi...
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作者：Li, Liang; Wu, Chih-Hsien; Ning, Jing; Huang, Xuelin; Shih, Ya-Chen Tina; Shen, Yu
作者单位：University of Texas System; UTMD Anderson Cancer Center; University of Texas System; UTMD Anderson Cancer Center
摘要：Estimating the average monthly medical costs from disease diagnosis to a terminal event such as death for an incident cohort of patients is a topic of immense interest to researchers in health policy and health economics because patterns of average monthly costs over time reveal how medical costs vary across phases of care. The statistical challenges to estimating monthly medical costs longitudinally are multifold; the longitudinal cost trajectory (formed by plotting the average monthly costs ...
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作者：Chan, Joshua; Leon-Gonzalez, Roberto; Strachan, Rodney W.
作者单位：University of Technology Sydney; National Graduate Institute for Policy Studies; University of Queensland
摘要：Factor models are used in a wide range of areas. Two issues with Bayesian versions of these models are a lack of invariance to ordering of and scaling of the variables and computational inefficiency. This article develops invariant and efficient Bayesian methods for estimating static factor models. This approach leads to inference that does not depend upon the ordering or scaling of the variables, and we provide arguments to explain this invariance. Beginning from identified parameters which a...
