Two-stage predictor substitution (2SPS) and the two-stage residual inclusion (2SRI) are two approaches to instrumental variable (IV) analysis. While 2SPS and 2SRI with linear models are well-studied methods of causal inference, the properties of 2SPS and 2SRI for logistic binary outcomes have...

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...

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...

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...

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...

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...

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...

During Peter Drucker’s talk entitled "From Computer Literacy to Information Literacy" he discusses information systems and how they impact individual enterprises and workers. During his lecture, he talks about: the changing labor force, organization structure, command and control structure,...

Accountable Care Organizations are developing in the United States as a result of the Patient Protection and Affordable Care Act. A study is needed to evaluate an emerging issue of ACOs, quality improvement infrastructure, and the pharmaceutical industry. The convergence of these topics has not...

The relationships between risk and performance were tested employing within and between analyses at the level of strategic groups in three different industries. As hypothesized, systematic risk did not exhibit a consistent relationship with performance. By contrast, all of the total...