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The receiver operating characteristic (ROC) curve may be used to evaluate the performance of a biomarker measured on continuous scale to predict disease status or clinical condition. Motivated by the need for novel study designs with better estimation efficiency and reduced study cost, we...
Persistent link: https://www.econbiz.de/10009468304
The area under a ROC curve (AUC) and partial area under a ROC curve (pAUC) are important summary measures useful in assessing the accuracy of a diagnostic test or a biomarker in discriminating true disease status. We consider nonparametric estimation of AUC and pAUC under a test-result-dependent...
Persistent link: https://www.econbiz.de/10009468312
When data are missing at random, the missing-data mechanism can be ignored but this assumption is not always intuitive for general patterns of missing data. In part I, we consider maximum likelihood (ML) estimation for a non-ignorable mechanism which is called almost missing at random (AMAR). We...
Persistent link: https://www.econbiz.de/10009476653
Asymptotic expansions for the null distribution of thelogrank statistic and its distribution under local proportionalhazards alternatives are developed in the case of iid observations.The results, which are derived from the work of Gu (1992) andTaniguchi (1992), are easy to interpret, and...
Persistent link: https://www.econbiz.de/10009477088
The analysis of longitudinal repeated measures data is frequently complicated by missing data due to informative dropout. We describe a mixture model for joint distribution for longitudinal repeated measures, where the dropout distribution may be continuous and the dependence between response...
Persistent link: https://www.econbiz.de/10009477333
Recent results for case-control sampling suggest when the covariate distribution is constrained by gene-environment independence, semiparametric estimation exploiting such independence yields a great deal of efficiency gain. We consider the efficient estimation of the treatment-biomarker...
Persistent link: https://www.econbiz.de/10009483614
In 2001, the ACM and IEEE Computing Curriculum stated that it was necessary to address "the need to develop implementation models that are international in scope and could be practiced in universities around the world." With increasing connectivity through the internet, the move towards a global...
Persistent link: https://www.econbiz.de/10009485610
A novel coronavirus was reported to the World Health Organization (WHO) in China on 31 December 2019. The WHO named the disease COVID-19 on 11 February 2020. As of 26 February 2020, the disease has been detected on all continents, except for Antarctica. Daily updates on COVID-19 since early...
Persistent link: https://www.econbiz.de/10012611275
Due to the Corona pandemic, it was necessary to cancel the conference "Positionality Reloaded: Dimensions of Reflexivity in the Relationship of Science and Society" at short notice. At the time, in May 2020, it was quite uncertain how far-reaching the consequences of the pandemic would be. This...
Persistent link: https://www.econbiz.de/10012793756
Randomised controlled or clinical trials (RCTs) are generally viewed as the most reliable method to draw causal inference as to the effects of a treatment, as they should guarantee that the individuals being compared differ only in terms of their exposure to the treatment of interest. This 'gold...
Persistent link: https://www.econbiz.de/10011786837