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作者：Claeskens, G.; Krivobokova, T.; Opsomer, J. D.
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作者：Stallard, Nigel; Kimani, Peter K.
作者单位：University of Warwick
摘要：Multi-arm multi-stage clinical trials compare several experimental treatments with a control treatment, with poorly performing treatments dropped at interim analyses. This leads to inferential challenges, including the construction of unbiased treatment effect estimators. A number of estimators which are unbiased conditional on treatment selection have been proposed, but are specific to certain selection rules, may ignore the comparison to the control and are not all minimum variance. We obtai...
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作者：Yang, S.; Ding, P.
作者单位：North Carolina State University; University of California System; University of California Berkeley
摘要：Causal inference with observational studies often relies on the assumptions of unconfoundedness and overlap of covariate distributions in different treatment groups. The overlap assumption is violated when some units have propensity scores close to 0 or 1, so both practical and theoretical researchers suggest dropping units with extreme estimated propensity scores. However, existing trimming methods often do not incorporate the uncertainty in this design stage and restrict inference to only th...
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作者：Chang, Jinyuan; Delaigle, Aurore; Hall, Peter; Tang, Chengyong
作者单位：Southwestern University of Finance & Economics - China; University of Melbourne; Pennsylvania Commonwealth System of Higher Education (PCSHE); Temple University
摘要：Data observed at a high sampling frequency are typically assumed to be an additive composite of a relatively slow-varying continuous-time component, a latent stochastic process or smooth random function, and measurement error. Supposing that the latent component is an Ito diffusion process, we propose to estimate the measurement error density function by applying a deconvolution technique with appropriate localization. Our estimator, which does not require equally-spaced observed times, is con...
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作者：Diao, Guoqing; Zeng, Donglin; Ke, Chunlei; Ma, Haijun; Jiang, Qi; Ibrahim, Joseph G.
作者单位：George Mason University; University of North Carolina; University of North Carolina Chapel Hill; Amgen
摘要：Composite endpoints with censored data are commonly used as study outcomes in clinical trials. For example, progression-free survival is a widely used composite endpoint, with disease progression and death as the two components. Progression-free survival time is often defined as the time from randomization to the earlier occurrence of disease progression or death from any cause. The censoring times of the two components could be different for patients not experiencing the endpoint event. Conve...
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作者：Mondal, D.
作者单位：Oregon State University
摘要：This paper discusses edge correction for a large class of conditional and intrinsic autoregressions on two-dimensional finite regular arrays. The proposed method includes a novel reparameterization, retains the simple neighbourhood structure, ensures the nonnegative definiteness of the precision matrix, and enables scalable matrix-free statistical computation. The edge correction provides new insight into how higher-order differencing enters into the precision matrix of a conditional autoregre...
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作者：Johndrow, J. E.; Lum, K.; Dunson, D. B.
作者单位：Stanford University; Duke University
摘要：There has been substantial recent interest in record linkage, where one attempts to group the records pertaining to the same entities from one or more large databases that lack unique identifiers. This can be viewed as a type of microclustering, with few observations per cluster and a very large number of clusters. We show that the problem is fundamentally hard from a theoretical perspective and, even in idealized cases, accurate entity resolution is effectively impossible unless the number of...
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作者：Xia, Yin; Cai, T. Tony; Li, Hongzhe
作者单位：Fudan University; University of Pennsylvania; University of Pennsylvania
摘要：Multivariate regression with high-dimensional covariates has many applications in genomic and genetic research, in which some covariates are expected to be associated with multiple responses. This paper considers joint testing for regression coefficients over multiple responses and develops simultaneous testing methods with false discovery rate control. The test statistic is based on inverse regression and bias-corrected group lasso estimates of the regression coefficients and is shown to have...
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作者：Zhao, Jiwei; Ma, Yanyuan
作者单位：State University of New York (SUNY) System; University at Buffalo, SUNY; Pennsylvania Commonwealth System of Higher Education (PCSHE); Pennsylvania State University; Pennsylvania State University - University Park
摘要：Tang et al. (2003) considered a regression model with missing response, where the missingness mechanism depends on the value of the response variable and hence is nonignorable. They proposed three pseudolikelihood estimators, based on different treatments of the probability distribution of the completely observed covariates. The first assumes the distribution of the covariate to be known, the second estimates this distribution parametrically, and the third estimates the distribution nonparamet...
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作者：Massam, H.; Li, Q.; Gao, X.
作者单位：York University - Canada; Sun Yat Sen University
摘要：Graphical Gaussian models with edge and vertex symmetries were introduced by Hojsgaard & Lauritzen (2008), who gave an algorithm for computing the maximum likelihood estimate of the precision matrix for such models. In this paper, we take a Bayesian approach to its estimation. We consider only models with symmetry constraints and which thus form a natural exponential family with the precision matrix as the canonical parameter. We identify the Diaconis-Ylvisaker conjugate prior for these models...
