Donald Hedeker Office: 5841 S. Maryland Avenue, Room W254 Phone: Email
Professor of Biostatistics in the Department of Public Health Sciences

Donald Hedeker’s main area of expertise is in the development and use of advanced statistical methods for clustered and longitudinal data, with particular emphasis on mixed-effects models. He is the primary author of four freeware computer programs for mixed-effects analysis: MIXREG for normal-theory models, MIXOR for dichotomous and ordinal outcomes, MIXNO for nominal outcomes, and MIXPREG for counts.

In 2000, Hedeker was named a fellow of the American Statistical Association, the highest honor in his field. He was also recognized as a University Scholar by the University of Illinois that same year. He serves as an associate editor for Statistics in Medicine and the Journal of Statistical Software. He has been the principal investigator (PI), co-PI, or co-investigator on many research grants funded by the National Institutes of Health (NIH) and the Centers for Disease Control and Prevention.


  • Mixed-effects models for clustered and longitudinal data analysis, especially ordinal outcomes
  • Missing data in longitudinal studies
  • Models for intensive longitudinal data, particularly data from Ecological Momentary Assessment (EMA) and mHealth studies
  • Software development and computational statistics
  • Tobacco and addictions research