In population based genetic association studies, confounding due to population stratification (PS) arises when differences in both allele and disease frequencies exist in a population of mixed racial/ethnic subpopulations. Propensity scores are often used to address confounding in observational...

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...

This research is concerned with estimating the relationship between the occurrence of metastases and the size of primary cancers. We are interested in finding the distribution functions of tumor sizes at the points of nodal metastatic and distant metastatic transitions. Understanding the...

The random field model has been applied to model spatial heterogeneity for spatial data in many applications. The purpose of this dissertation is to explore statistical properties of noisy spatial data through estimation of the Gaussian random field. Large sample properties of the Maximum...

In public health studies, it is common for exposure status to be misclassified. In this dissertation, statistical models to adjust for misclassification will be proposed to address four related questions of interest.The first question focuses on exploring the association between a disease and...

En génétique des populations, les modèles sont souvent complexes ce qui rend l'évaluation de la vraisemblance difficile, si ce n'est impossible. En revanche, des mécanismes de génération de données sont parfois disponibles ce qui explique pourquoi les méthodes d'inférence bayésienne...

Randomized clinical trials are commonly conducted in pharmaceutical companies and medical research institutes to evaluate a certain intervention effect. Standard intention-to-treat (ITT) analysis is routinely performed to test if there is a difference in outcome between the randomized groups....