Positions: Full staff, Quantitative Health Sciences, The Cleveland Clinic Foundation, 2005-present Full Staff, Biostatistics and Epidemiology, The Cleveland Clinic Foundation, 1994-2004 Education: PhD, Quantitative Psychology (applied statistics for the behavioral and biological sciences), University of North Carolina, Chapel Hill, NC, 1975

Key Interests:
With respect to statistics research, Ralph's distributionally robust test for variability differences is now in the SAS System (PROC GLM) and JMP software. His current work in power analysis is focused on the production of UnifyPow, a freeware module/macro for the SAS System.

Selected Publications:
O'Brien RG (1979), "A General ANOVA Method for Robust Tests of Additive Models for Variance." Journal of the American Statistical Association, 74:877-881.

Walker E, O'Brien RG (1992), "Using Restricted Least-Squares to Delineate the Effects of Misspecification in Linear Models." The Statistician, 41:467-476.

O'Brien RG, Muller KE (1993), "Unified Power Analysis for t Tests Through Multivariate Hypotheses," in Applied Analysis of Variance in the Behavioral Sciences, Edwards LK (Ed), New York:Marcel Dekker, pp 297- 344. [You may download an Acrobat file giving my final manuscript for this chapter, albeit with a revised appendix to update the information on the freeware.]

Huang D, O'Brien RG, Harmon E, Aull L, Reents S, Visser J, Shieh G, Hendeles L. (1993), "Does Aminophylline Provide Benefit for Adults Hospitalized with an Acute Exacerbation of Asthma?" Annals of Internal Medicine, 119:1155-1160.

O'Brien RG, Heft MW (1995), "New Discrimination Indexes and Models for Studying Sensory Functioning in Aging." Journal of Applied Statistics, 22:9-27.

O'Brien RG (1998), "A Tour of UnifyPow: a SAS Module/Macro for Sample-Size Analysis," Proceedings of the 23rd Annual SAS Users Group International Conference, Cary NC: SAS Institute Inc., 1346-1355. [You may download the current update of this paper. (An Acrobat file)]