R.J. Wirth is President and a managing partner at VPG and leads its team of scientists and software engineers in day-to-day operation. This includes project coordination, psychometric analysis, and software development. In addition to these duties, Dr. Wirth regularly participates in projects in his capacity as a quantitative psychologist/psychometrician. Dr. Wirth trained in the L. L. Thurstone Psychometric Lab, receiving his PhD in Quantitative Psychology from the University of North Carolina – Chapel Hill. Prior to taking over the daily operations of VPG, Dr. Wirth held research positions at the Frank Porter Graham Child Development Institute at The University of North Carolina and in the School of Medicine at the University of Washington.
Dr. Wirth’s research focuses on modern psychometrics with an emphasis on measurement invariance in longitudinal models within the factor analysis, structural equation, and IRT frameworks. He has published numerous book chapters and journal articles appearing in outlets such as Child Development, Health Psychology, Journal of Abnormal Psychology, Medical Care, Psychological Assessment, and Psychological Methods. He recently joined the North Carolina Technology Association as a member of the Board of Advisors.