We consider using observational data to estimate the effect of a treatment on disease recurrence, when the decision to initiate treatment is based on longitudinal factors associated with the risk of recurrence. The effect of salvage androgen deprivation therapy (SADT) on the risk of recurrence...

The weighted Kaplan–Meier (WKM) estimator is often used to incorporate prognostic covariates into survival analysis to improve efficiency and correct for potential bias. In this paper, we generalize the WKM estimator to handle a situation with multiple prognostic covariates and...

The semiparametric linear model is an important alternative to the Cox proportional hazards model for censored survival outcomes. In this dissertation, we provide some new insights for the parameter estimators and their asymptotic properties in the semiparametric linear model with censored...

This paper addresses the problem of estimating the tail index Α of distributions with heavy, Pareto-type tails for dependent data, that is of interest in the areas of finance, insurance, environmental monitoring and teletraffic analysis. A novel approach based on the max self-similarity scaling...

Increasingly often, problems in modern medicine, quantitative finance, or social-networking involve tens of thousands of variables that interact with each other and jointly evolve over time. The states of these variables may correspond to the phenotype of a particular individual, the price of a...

Despite their widespread use as predictors of the spot price of oil, oil futures prices tend to be less accurate in the mean-squared prediction error sense than no-change forecasts. This result is driven by the variability of the futures price about the spot price, as captured by the oil futures...

Linkage and association analysis are both tools for mapping the locations of genes responsible for human traits. A common approach for quantitative trait linkage analysis in human pedigrees involves the use of variance component models. In the first part of this dissertation, I extended the...

This dissertation considers several modeling problems involvingclustered longitudinal data. Interest focuses on the associationstructure rather than the means and, in particular, on its change overtime. Concentration on this non-stationary, or ``dynamic'' aspect of theassociation structure is...

Estimation of flow volumes in computer networks involves the use of data that are either highly aggregated or fairly noisy. We address several conceptual and practical aspects of the use of such data for flow volume estimation in this work. The results presented are often of general statistical...

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...