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作者：Gertheiss, Jan; Tutz, Gerhard
作者单位：University of Munich
摘要：Shrinking methods in regression analysis are usually designed for metric predictors. In this article, however, shrinkage methods for categorial predictors are proposed. As an application we consider data from the Munich rent standard, where, for example, urban districts are treated as a categorial predictor. If independent variables are categorial, some modifications to usual shrinking procedures are necessary. Two L-1-penalty based methods for factor selection and clustering of categories are...
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作者：Berrocal, Veronica J.; Gelfand, Alan E.; Holland, David M.
作者单位：University of Michigan System; University of Michigan; Duke University; United States Environmental Protection Agency
摘要：Ozone and particulate matter, PM2.5, are co-pollutants that have long been associated with increased public health risks. Information on concentration levels for both pollutants comes from two sources: monitoring sites and output from complex numerical models that produce concentration surfaces over large spatial regions. In this paper, we offer a fully-model-based approach for fusing these two sources of information for the pair of co-pollutants which is computationally feasible over large sp...
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作者：Zhang, Tingting; Kou, S. C.
作者单位：University of Virginia
摘要：Doubly stochastic Poisson processes, also known as the Cox processes, frequently occur in various scientific fields. In this article, motivated primarily by analyzing Cox process data in biophysics, we propose a nonparametric kernel-based inference method. We conduct a detailed study, including an asymptotic analysis, of the proposed method, and provide guidelines for its practical use, introducing a fast and stable regression method for bandwidth selection. We apply our method to real photon ...
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作者：Meinshausen, Nicolai
作者单位：University of Oxford
摘要：When choosing a suitable technique for regression and classification with multivariate predictor variables, one is often faced with a tradeoff between interpretability and high predictive accuracy. To give a classical example, classification and regression trees are easy to understand and interpret. Tree ensembles like Random Forests provide usually more accurate predictions. Yet tree ensembles are also more difficult to analyze than single trees and are often criticized, perhaps unfairly, as ...
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作者：Bissantz, Nicolai; Holzmann, Hajo; Pawlak, Miroslaw
作者单位：Ruhr University Bochum; Philipps University Marburg; University of Manitoba
摘要：A method for estimating the axis of reflectional symmetry of an image f (x, y) on the unit disc D = {(x, y) : x(2) + y(2) <= 1} is proposed, given that noisy data of f (x, y) are observed on a discrete grid of edge width Delta. Our estimation procedure is based on minimizing over beta is an element of [0, pi) the L-2 distance between empirical versions of f and tau(beta)f, the image of f after reflection at the axis along (cos beta, sin beta). Here, f and tau(beta)f are estimated using truncat...
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作者：Francis, Brian; Dittrich, Regina; Hatzinger, Reinhold
作者单位：Lancaster University; Vienna University of Economics & Business
摘要：This paper is motivated by a Eurobarometer survey on science knowledge. As part of the survey, respondents were asked to rank sources of science information in order of importance. The official statistical analysis of these data however failed to use the complete ranking information. We instead propose a method which treats ranked data as a set of paired comparisons which places the problem in the standard framework of generalized linear models and also allows respondent covariates to be incor...
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作者：Ghosh, Samiran
作者单位：Purdue University System; Purdue University; Purdue University in Indianapolis
摘要：This paper describes a novel approach based on proportional imputation when identical units produced in a batch have random but independent installation and failure times. The current problem is motivated by a real life industrial production-delivery supply chain where identical units are shipped after production to a third party warehouse and then sold at a future date for possible installation. Due to practical limitations, at any given time point, the exact installation as well as the failu...
