Showing 1 - 10 of 24
Risk difference is an important measure of effect size in biostatistics, for both randomised and observational studies. The natural way to adjust risk differences for potential confounders is to use an additive binomial model, which is a binomial generalised linear model with an identity link...
Persistent link: https://www.econbiz.de/10010906924
Let T1 and T2 be the survival times of patients randomized to, respectively, two treatment groups. The probability P(T1T2) may be used as a measure on the effect of treatments in a randomized clinical trial. With potentially censored data observed and assuming that the density functions of...
Persistent link: https://www.econbiz.de/10010871358
In Balabdaoui, Rufibach, and Wellner (2009), pointwise asymptotic theory was developed for the nonparametric maximum likelihood estimator of a log-concave density. Here, the practical aspects of their results are explored. Namely, the theory is used to develop pointwise confidence intervals for...
Persistent link: https://www.econbiz.de/10010871360
A non-randomized triangular design has been shown to be more efficient than the conventional random response model in estimating the prevalence of sensitive attributes in surveys. Since most surveys focus on estimation, herein we derive sample size formulas for estimation of prevalence and a...
Persistent link: https://www.econbiz.de/10010871374
Given a finite population consisting of N elements, it is desired to obtain confidence intervals for (t/N)th quantile x(t) of the population based on the randomized nomination sampling (RNS) design. Three without replacement sampling protocols are described and procedures for constructing...
Persistent link: https://www.econbiz.de/10010871392
As an important extension of the regular kappa statistic, the weighted kappa statistic has been widely used to assess the agreement between two procedures for independent matched-pair ordinal data. For clustered matched-pair ordinal data, based on the delta method and sampling techniques, a...
Persistent link: https://www.econbiz.de/10011117701
Confidence interval construction for the Youden index of a diagnostic test based on partially validated series with dichotomous response is considered in this article. Using the Wald and Agresti-Coull, the Wilson score, logit-transformation and the method of variance estimates recovery, eight...
Persistent link: https://www.econbiz.de/10011191021
It is desirable to estimate disease prevalence based on data collected by a gold standard test, but such a test is often limited due to cost and ethical considerations. Data with partial validation series thus become an alternative. The construction of confidence intervals for disease prevalence...
Persistent link: https://www.econbiz.de/10010574468
In diagnostic studies, the receiver operating characteristic (ROC) curve and the area under the ROC curve are important tools in assessing the utility of biomarkers in discriminating between non-diseased and diseased populations. For classifying a patient into the non-diseased or diseased group,...
Persistent link: https://www.econbiz.de/10010577729
We study generalized single-index models and propose an efficient equation for estimating the index parameter and unknown link function, deriving a quasi-likelihood-based maximum empirical likelihood estimator (QLMELE) of the index parameter. We then establish an efficient confidence region for...
Persistent link: https://www.econbiz.de/10011056470