Salivary cortisol and prefrontal cortical thickness in middle-aged men: A twin study. - William S. Kremen; Robert C. O'Brien; Matthew S. Panizzon; Elizabeth Prom-Wormley; Lindon J. Eaves; Seth A. Eisen; Lisa T. Eyler; Richard L. Hauger; Christine Fennema-Notestine; Bruce Fischl; Michael D. Grant; Dirk H. Hellhammer; et al. (NeuroImage, 2010)

A random forests quantile classifier for class imbalanced data. - Robert C. O'Brien; Hemant Ishwaran (Pattern Recognit., 2019)