The public policy mantra of the moment is metrics -- measuring how we're doing in order to do better. The State Bar of Michigan is on board (read our ringing endorsement of the need for more and better data and analysis to improve Michigan's court system in the Judicial Crossroads Task Force report). But we need to keep reminding ourselves to be very, very careful that what we're measuring is what really matters. Jonah Lehrer in his Frontal Cortex blog makes the point, as usual, through an entertaining and thought-provoking illustration. Read "Measurements That Mislead."