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作者：Brannath, W; Posch, M; Bauer, P
作者单位：University of Vienna
摘要：We present a method that extends the flexibility of adaptive designs to the number of interim analyses and to the choice of decision boundaries. At each stage of the trial, the design of the next stage can be determined using all of the information gathered so far. Additionally, one can specify the next stage as the final stage or can plan a further interim analysis. The method is based on a recursive application of the two-stage combination tests for p values. The crucial point is the appropr...
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作者：Lin, L; Hedayat, AS; Sinha, B; Yang, M
作者单位：University of Illinois System; University of Illinois Chicago; University of Illinois Chicago Hospital; Indian Statistical Institute; Indian Statistical Institute Kolkata
摘要：Measurements of agreement are needed to assess the acceptability of a new or generic process, methodology, and formulation in areas of laboratory performance, instrument or assay validation, method comparisons, statistical process control, goodness of fit, and individual bioequivalence, In all of these areas, one needs measurements that capture a large proportion of data that are within a meaningful boundary from target values. Target values can be considered random (measured with error) or fi...
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作者：Fraley, C; Raftery, AE
作者单位：University of Washington; University of Washington Seattle
摘要：Cluster analysis is the automated search for groups of related observations in a dataset. Most clustering done in practice is based largely on heuristic but intuitively reasonable procedures, and most clustering methods available in commercial software are also of this type. However, there is little systematic guidance associated with these methods for solving important practical questions that arise in cluster analysis, such as how many clusters are there, which clustering method should be us...
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作者：Maronna, RA; Yohai, VJ
作者单位：National University of La Plata; University of Buenos Aires; Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET)
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作者：Ozturk, O
作者单位：University System of Ohio; Ohio State University
摘要：The use of statistical methods based on ranked-set sampling can lead to a substantial improvement over analog methods associated with simple random sampling schemes. This article develops a rank-based estimator and testing procedures for linear models for ranked-set samples. The estimator is defined as the minimizer of the rank dispersion function with Wilcoxon scores. It is shown that the estimator of the regression parameter is asymptotically normal and has higher Pitman asymptotic efficienc...
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作者：Elliott, MR; Raghunathan, TE; Shope, JT
作者单位：University of Pennsylvania; University of Michigan System; University of Michigan; University of Michigan System; University of Michigan
摘要：The driving history records of a sample of 13,794 Michigan public school students were followed for up to 13 years from their initial time-of-license to determine the separate effects of duration of licensure and delay of licensure on risk of crash. We propose a subject-specific lognormal accelerated failure time to model the expected time-to-crash as a function of age at time of licensure, duration of licensure, and a set of control covariates. When multiple time-to-crash measures are observe...
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作者：Inoue, LYT; Parmigiani, G
作者单位：University of Texas System; UTMD Anderson Cancer Center; Johns Hopkins University; Johns Hopkins University; Johns Hopkins University
摘要：Studies of time-to-event are often conducted using follow-up sessions with subjects at risk. When these sessions must be widely spaced, their timing can significantly affect the efficiency of a study design. In this article we analyze the optimal timing of follow-up from a Bayesian decision theoretic standpoint. The article has two goals: (1) to develop the necessary distributional theory and computational approaches to determine optimal sequential and nonsequential follow-up schedules in the ...
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作者：Zhuang, J; Ogata, Y; Vere-Jones, D
作者单位：Graduate University for Advanced Studies - Japan; Research Organization of Information & Systems (ROIS); Institute of Statistical Mathematics (ISM) - Japan; Victoria University Wellington
摘要：This article is concerned with objective estimation of the spatial intensity function of the background earthquake occurrences from an earthquake catalog that includes numerous clustered events in space and time, and also with an algorithm for producing declustered catalogs from the original catalog. A space-time branching process model (the ETAS model) is used for describing how each event generates offspring events. It is shown that the background intensity function can be evaluated if the t...
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作者：van de Wiel, MA
作者单位：Eindhoven University of Technology
摘要：Computation of exact p values of multiple comparisons rank statistics is often a very time-consuming task. In some cases approximations are available, but they are often unsatisfactory when samples are small or the number of ties is large. Some existing tables of exact critical values contain errors and are limited to small samples without ties and to Wilcoxon scores. Therefore, this article proposes a new algorithm to compute exact p values of generalized Steel statistics for one-way classifi...
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作者：Saltelli, A; Tarantola, S
作者单位：European Commission Joint Research Centre; EC JRC ISPRA Site
摘要：This article deals with global quantitative sensitivity analysis of the Level E model, a computer code used in safety assessment for nuclear waste disposal. The Level E code has been the Subject of two international benchmarks of risk assessment codes and Monte Carlo methods and is well known in the literature. We discuss the Level E model with reference to two different settings. In the first setting, the objective is to find the input factor that drives most of the output variance. In the se...
