I am interested in analyzing expert or professional judgment under conditions of complexity and uncertainty. Why are some judges more accurate than others? How can judgments be improved? I use Brunswik's lens model framework and the lens model equation to analyze various components of expert skill. I am particularly interested in practical applications of judgment and decision research to public policy issues and to improving professional judgment. Recently, I have become increasingly interested in observing and studying judgment and decision making in natural settings.For more information, see the Center for Policy Research and the home page for my course "Seminar on Judgment and Decision making Behavior."