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作者：Sun, Fasheng; Tang, Boxin
作者单位：Northeast Normal University - China; Simon Fraser University
摘要：Orthogonal Latin hypercubes provide a class of useful designs for computer experiments. Among the available methods for constructing such designs, the method of rotation is particularly prominent due to its theoretical appeal as well as its space-filling properties. This paper presents a general method of rotation for constructing orthogonal Latin hypercubes, making the rotation idea applicable to many more situations than the original method allows. In addition to general theoretical results,...
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作者：Binkiewicz, N.; Vogelstein, J. T.; Rohe, K.
作者单位：University of Wisconsin System; University of Wisconsin Madison; Johns Hopkins University
摘要：Biological and social systems consist of myriad interacting units. The interactions can be represented in the form of a graph or network. Measurements of these graphs can reveal the underlying structure of these interactions, which provides insight into the systems that generated the graphs. Moreover, in applications such as connectomics, social networks, and genomics, graph data are accompanied by contextualizing measures on each node. We utilize these node covariates to help uncover latent c...
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作者：Farewell, D. M.; Huang, C.; Didelez, V.
作者单位：Cardiff University; Cardiff University; Leibniz Association; Leibniz Institute for Prevention Research & Epidemiology (BIPS)
摘要：Likelihood factors that can be disregarded for inference are termed ignorable. We demonstrate that close ties exist between ignorability and identification of causal effects by covariate adjustment. A graphical condition, stability, plays a role analogous to that of missingness at random, but is applicable to general longitudinal data. Our formulation of ignorability does not depend on any notion of missing data, so is appealing in situations where missing data may not actually exist. Several ...
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作者：Wang, Junhui; Shen, Xiaotong; Sun, Yiwen; Qu, Annie
作者单位：City University of Hong Kong; University of Minnesota System; University of Minnesota Twin Cities; University of Illinois System; University of Illinois Urbana-Champaign
摘要：Automatic tagging by key words and phrases is important in multi-label classification of a document. In this paper, we first introduce a tagging loss to measure the discrepancy between predicted and actual tag sets, which is expressed in terms of a sum of weighted pairwise margins between two tags by their degree of similarity. We then construct a regularized empirical loss to incorporate linguistic knowledge, and identify a tagger maximizing the separations between the pairwise margins. One s...
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作者：Linero, A. R.
作者单位：State University System of Florida; Florida State University
摘要：In longitudinal clinical trials, one often encounters missingness that is thought to be nonignorable. Such missingness introduces identifiability issues, resulting in causal effects being nonparametrically unidentified; it is then prudent to conduct a sensitivity analysis to assess how much of the inference is being driven by untestable assumptions needed to identify the effects of interest. We introduce a Bayesian nonparametric framework for conducting inference in the presence of nonignorabl...
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作者：Chen, Sixia; Haziza, David
作者单位：University of Oklahoma System; University of Oklahoma Health Sciences Center; Universite de Montreal
摘要：Item nonresponse in surveys is often treated through some form of imputation. We introduce multiply robust imputation in finite population sampling. This is closely related to multiple robustness, which extends double robustness. In practice, multiple nonresponse models and multiple imputation models may be fitted, each involving different subsets of covariates and possibly different link functions. An imputation procedure is said to be multiply robust if the resulting estimator is consistent ...
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作者：Holmes, C. C.; Walker, S. G.
作者单位：University of Oxford; University of Texas System; University of Texas Austin
摘要：Bayesian robustness under model misspecification is a current area of active research. Among recent ideas is that of raising the likelihood function to a power. In this paper we discuss the choice of appropriate power and provide examples.
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作者：Kong, Xin-Bing
作者单位：Nanjing Audit University
摘要：In this paper, we introduce a local principal component analysis approach to determining the number of common factors of a continuous-time factor model with time-varying factor loadings using high-frequency data. The model is approximated locally on shrinking blocks using discrete-time factor models. The number of common factors is estimated by minimizing the penalized aggregated mean squared residual error over all shrinking blocks. While the local mean squared residual error on each block co...
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作者：Ren, Haojie; Chen, Nan; Zou, Changliang
作者单位：Nankai University; National University of Singapore
摘要：We propose a procedure based on a high-breakdown mean function estimator to detect outliers in functional data. The robust estimator is obtained from a clean subset of observations, excluding potential outliers, by minimizing the least-trimmed-squares projection coefficients after functional principal component analysis. A threshold rule based on the asymptotic distribution of the functional score-based distance robustly controls the false positive rate and detects outliers effectively. Furthe...
