نتایج جستجو برای: wald test

تعداد نتایج: 813470  

Journal: :Statistics in medicine 2016
Tobias Mütze Axel Munk Tim Friede

A three-arm clinical trial design with an experimental treatment, an active control, and a placebo control, commonly referred to as the gold standard design, enables testing of non-inferiority or superiority of the experimental treatment compared with the active control. In this paper, we propose methods for designing and analyzing three-arm trials with negative binomially distributed endpoints...

2008
Pierre Perron Yohei Yamamoto

Elliott and Müller (2006) considered the problem of testing for general types of parameter variations, including infrequent breaks. They developed a framework that yields optimal tests, in the sense that they nearly attain some local Gaussian power envelop. The main ingredient in their setup is that the variance of the process generating the changes in the parameters must go to zero at a fast r...

2005
Abraham Wald Hans Schneeweiss

This paper grew out of a lecture presented at the 54th Session of the International Statistical Institute in Berlin, August 13 20, 2003, Schneeweiss (2003). It intends not only to outline the eventful life of Abraham Wald (1902 1950) in Austria and in the United States but also to present his extensive scientific work. In particular, the two main subjects, where he earned most of his fame, are ...

Journal: :Computational Statistics & Data Analysis 2009
Tonglin Zhang Ge Lin

The likelihood ratio spatial scan statistic has been widely used in spatial disease surveillance and spatial cluster detection applications. In order to better understand cluster mechanisms, an equivalent model-based approach is proposed to the spatial scan statistic that unifies currently loosely coupled methods for including ecological covariates in the spatial scan test. In addition, the uti...

2003
Myunghwan Seo

There is a growing literature on unit root testing in threshold autoregressive models. This paper makes two contributions to the literature. First, an asymptotic theory is developed for unit root testing in a threshold autoregression, in which the errors are allowed to be dependent and heterogeneous, and the lagged level of the dependent variable is employed as the threshold variable. The asymp...

2003
Moulinath Banerjee Jon A. Wellner

In this paper we introduce three natural “score statistics” for testing the hypothesis that F (t0) takes on a fixed value in the context of nonparametric inference with current status data. These three new test statistics have natural intepretations in terms of certain (weighted) L2 distances, and are also connected to natural “one-sided” scores. We compare these new test statistics with an ana...

Journal: :Statistics in medicine 2011
Philip M Westgate Thomas M Braun

Group Randomized Trials (GRTs) randomize groups of people to treatment or control arms instead of individually randomizing subjects. When each subject has a binary outcome, over-dispersed binomial data may result, quantified as an intra-cluster correlation (ICC). Typically, GRTs have a small number, bin, of independent clusters, each of which can be quite large. Treating the ICC as a nuisance p...

Journal: :Statistica Sinica 2013
Zhigang Li Ian W McKeague

We consider the problem of calculating power and sample size for tests based on generalized estimating equations (GEE), that arise in studies involving clustered or correlated data (e.g., longitudinal studies and sibling studies). Previous approaches approximate the power of such tests using the asymptotic behavior of the test statistics under fixed alternatives. We develop a more accurate appr...

2014
Martina Kottas Oliver Kuss Antonia Zapf

BACKGROUND The area under the receiver operating characteristic (ROC) curve, referred to as the AUC, is an appropriate measure for describing the overall accuracy of a diagnostic test or a biomarker in early phase trials without having to choose a threshold. There are many approaches for estimating the confidence interval for the AUC. However, all are relatively complicated to implement. Furthe...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید