Professor Hedges’ research interests are in the development and application of statistical methods for the social, medical, and biological sciences. One major are of interest is the combination of results across studies to draw general conclusions (meta-analysis). Another major area of research is the design and analysis of social experiments. He works on the development of statistical methods in both of these areas and their application to policy research, particularly education policy. Prof. Hedges also works on the role of uncertainty in cognitive science, trying to understand how human cognition is shaped by the fact that it involves processing of information memory and perception that is inherently uncertain. Finally, he works on the demography of human abilities, including the understanding of differences between social groups and variation of abilities and measured achievement.