His research is in statistical methods for the problems in the biological sciences that lie at the forefront of the Department of Statistic's interdisciplinary efforts. His work has focused primarily on the utilization of Bayesian hierarchical methods which provide a natural framework to describe vast amounts of heterogeneity in data. His areas of research include diagnostic testing, plant and human genetics, protein structure, animal and insect population demographics, medical decision making, and disease modeling. Professor Craig serves as the Director of the Statistical Consulting Service (SCS) which provides advice for the statistical design of experiments and data analysis to University researchers.