Showing 41 - 50 of 130
A confidence interval for the between group variance is proposed which is deduced from Wald’s exact confidence interval for the ratio of the two variance components in the one-way random effects model and the exact confidence interval for the error variance resp. an unbiased estimator of the...
Persistent link: https://www.econbiz.de/10010316476
Die Umsetzung der Richtlinie zur Bestimmung der Anzahl von anorganischen faserförmigen Partikeln auf staubbelegten Filtern wurde in einem Ringversuch von VDI und DIN überprüft. Die Auswertung der Filter wurde zunächst in zwei Referenzlabors und danach in den teilnehmenden Prüflabors...
Persistent link: https://www.econbiz.de/10010316505
Persistent link: https://www.econbiz.de/10010316506
Concerning the actual significance level, we investigate the commonly used combined test procedures of meta-analysis, which contain the choice of the model, in which the analysis is carried out, and the commonly used tests for treatment effect in the fixed and random effects model, and some new...
Persistent link: https://www.econbiz.de/10010316525
In many applications we obtain test statistics by combining estimates from different experiments or studies. The usual combined estimator of the overall effect in independent studies leads to systematic overestimates of the significance level, see Li et al. (1994). This results in a great number...
Persistent link: https://www.econbiz.de/10010316553
Sind in einer statistischen Analyse mehr als eine Variationsursache zu berücksichtigen_ so zerfällt die Gesamtvariation in mehrere Komponenten. Für diese sind in der Regel auch Beziehungen oder Ordnungen bekannt. Aber keine der bekannten Schätztheorien ist in der Lage, diese Ordnungen auch...
Persistent link: https://www.econbiz.de/10010316569
A class of self-designing clinical trials is considered which according to an effective but simple, finite learning algorithm consists of automatically adaptively planned weighted group sequential trials with a decision about rejection of the null-hypothesis at each step, but the full...
Persistent link: https://www.econbiz.de/10010316573
Different estimation methods for covariance parameters in meta-analyses can result in conflicting p-values concerning the test of treatment effect. We propose a valid method to overcome this problem at least partially by introducing a new estimator for the standard deviation of the common...
Persistent link: https://www.econbiz.de/10010316597
In many fields of applications, test statistics are obtained by combining estimates from several experiments, studies or centres of a multicentre trial. The commonly used test procedure to judge the evidence of a common overall effect can result in a considerable overestimation of the...
Persistent link: https://www.econbiz.de/10010316638
In many meta-analysis cases the estimator of the overall effect in independent trials or experiments leads to unjustified significant results. This paper considers trials with two arms where the summary statistic of interest is either the mean difference or the risk difference. By using...
Persistent link: https://www.econbiz.de/10010316644