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作者：Zhang, Min; Strawderman, Robert L.; Cowen, Mark E.; T Wells, Martin
作者单位：Purdue University System; Purdue University; Cornell University; Saint Joseph Mercy Health System (SJMHS)
摘要：Profiling is currently an important, and hotly debated, topic in health care and other industries looking for ways to control costs, increase profitability, and increase service quality. Managed care in particular has seen a proliferation in the use of statistical profiling methodology, particularly with regard to monitoring expenditure data. This article focuses on the specific problem of developing statistical methods appropriate for profiling physician contributions to patient pharmacy expe...
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作者：Fernandez, Miguel A.; Rueda, Cristina; Salvador, Bonifacio
作者单位：Universidad de Valladolid
摘要：The most useful and broadly known rule in the classical two-group linear normal discriminant analysis is Anderson's rule. In this article we propose some alternative procedures that prove useful when prior constraints on the mean vectors are known. These rules are based on new estimators of the difference of means. We prove under mild conditions that the new rules perform better when the common covariance matrix is known. Simulated experiments show that the misclassification errors are lower f...
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作者：Finner, H.; Strassburger, K.
作者单位：Heinrich Heine University Dusseldorf; Leibniz Association; Deutsches Diabetes-Zentrum (DDZ)
摘要：In recent work we introduced a general, a weak, and a strong partitioning principles for the construction of multiple decision procedures as multiple testing or selection procedures. Partitioning principles can be viewed as natural extensions of the closure principle and sometimes yield more powerful decision procedures. In this article we consider the problem of establishing equivalence with the best with respect to k treatment means, where equivalence is defined in terms of a threshold value...
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作者：Wang, Lan; Akritas, Michael G.
作者单位：University of Minnesota System; University of Minnesota Twin Cities; Pennsylvania Commonwealth System of Higher Education (PCSHE); Pennsylvania State University; Pennsylvania State University - University Park
摘要：Traditional inference questions in the analysis of covariance mainly focus on comparing different factor levels by adjusting for the continuous covariates, which are believed to also exert a significant effect on the outcome variable. Testing hypotheses about the covariate effects, although of substantial interest in many applications, has received relatively limited study in the semiparametric/nonparametric setting. In the context of the fully nonparametric analysis of covariance model of Akr...
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作者：Tan, Zhiqiang
作者单位：Johns Hopkins University; Johns Hopkins Bloomberg School of Public Health
摘要：Drawing inferences about the effects of treatments and actions is a common challenge in economics, epidemiology, and other fields. We adopt Rubin's potential outcomes framework for causal inference and propose two methods serving complementary purposes. One can be used to estimate average causal effects, assuming no confounding given measured covariates. The other can be used to assess how the estimates might change under various departures from no confounding. Both methods are developed from ...
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作者：Hennerfeind, Andrea; Brezger, Andreas; Fahrmeir, Ludwig
作者单位：University of Munich
摘要：Survival data often contain small-area geographical or spatial information, such as the residence of individuals. In many cases, the impact of such spatial effects on hazard rates is of considerable substantive interest. Therefore, extensions of known survival or hazard rate models to spatial models have been suggested. Mostly, a spatial component is added to the usual linear predictor of the Cox model. In this article flexible continuous-time geoaddifive models are proposed, extending the Cox...
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作者：Lee, Chu-In Charles; Peng, Jianan; Liu, Lin
作者单位：Memorial University Newfoundland; Acadia University; University of California System; University of California San Diego
摘要：In many experiments, researchers are interested in comparing several treatment means with a control mean. When there are some treatments significantly better than the control, it is often of interest to evaluate the difference between the best treatment mean and the control mean and to identify the best treatment. In this article we derive lower confidence bounds for the aforementioned difference for the case that treatments are at least as effective as the control and for the case that no res...
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作者：Hannig, J.; Marron, J. S.
作者单位：Colorado State University System; Colorado State University Fort Collins; University of North Carolina; University of North Carolina Chapel Hill
摘要：SiZer is a powerful method for exploratory data analysis. In this article approximations to the distributions underlying the simultaneous statistical inference are investigated, and large improvements are made in the approximation using extreme value theory. This results in improved size, and also in an improved global inference version of SiZer. The main points are illustrated with real data and simulated examples.
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作者：Guan, Yongtao
作者单位：Yale University
摘要：We propose a new likelihood-based approach in fitting spatial point process models. A composite likelihood is first formed by adding some pairwise composite likelihood functions that are defined in terms of the second-order intensity function of the underlying process, and then used for estimating the unknown parameters. The estimation procedure is computationally simple and yields consistent and asymptotically normal estimators under some mild conditions. We demonstrate through a simulation s...
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作者：Galeano, Pedro; Pena, Daniel; Tsay, Ruey S.
作者单位：Universidad Carlos III de Madrid; University of Chicago
摘要：In this article we use projection pursuit methods to develop a procedure for detecting outliers in a multivariate time series. We show that testing for outliers in some projection directions can be more powerful than testing the multivariate series directly. The optimal directions for detecting outliers are found by numerical optimization of the kurtosis coefficient of the projected series. We propose an iterative procedure to detect and handle multiple outliers based on a univariate search in...
