The PI proposes to organize a multi-disciplinary symposium that will examine the roles that learning and instruction can play in how people reason with data: the kinds of representations they form, their understandings of measurement, of statistical noise, of graphical displays, and how they understand and use data to explain phenomena and make decisions. The proposed symposium will be the first of its kind to bring such a diverse group of junior and senior researchers together to forge common ground. It will allow them to exchange state-of-the-art work from their different disciplines, to seek converging results and common principles, and to discover research needs or gaps based on current work. At present, work in the disciplines of developmental psychology, statistics, decision analysis, and science and math education proceed with little interaction or sharing of insights. One of the focuses of the symposium is to bring current theoretical insights to bear on practice (in business and in the schools), as well as to make insights derived from the field available across field boundaries in order to allow it to advance the theoretical work.