My methodological work is mainly in the area of linear models, and my dissertation focused on nonparametric models for two-way random and mixed effects designs, for which I developed three hypothesis tests: fixed main effect (JASA), random main effect (J. Prob. and Stat.), and random interaction effect (Biometrics). Some of the distributions of the test statistics had complicated distributions, and I did a lot of work with resampling methods to estimate the distributions. I first published on an interesting use of resampling methods as applied to finding suitable weight functions for weighted log rank statistics when comparing two survival time distributions in this paper. I’ve continued to be interested in resampling methods in my current work as well.

In addition to this methodological work, I have done a lot of work in varied areas of application. Among other things, I’ve become interested in statistical applications to genetics. While at CMU, I was involved with a research group that is broadly working on understanding the genetic underpinnings of complex inherited diseases. In my particular problem, I needed reliable estimates of relatedness of the people in the sample. Our group developed a novel approach to this problem, called Treelet Covariance Smoothing (described here), for which I co-wrote this R package. The analysis we performed on a large sample of Swedish individuals to study the heritability of Autism resulted in this paper in Nature Genetics. This is joint work with Kathryn Roeder, Ann Lee, Bernie Devlin, and Bert Klei (Bernie and Bert are in the Western Psychiatric Institute and Clinic’s Computational Genetics Lab).

I have also been involved in several highly rewarding collaborations that have grown out of consulting projects. I’ve been actively involved with students in Penny Kris-Etherton’s lab in the Nutrition Department at Penn State, and I have been involved in ongoing military and air transportation noise research projects with psychoacoustics researchers (Edward Nykaza, Kathleen Hodgdon) from the U.S. Army Corps of Engineers and Penn State’s Applied Research Laboratory.