Freakonomics : a rogue economist explores the hidden side of everything / Steven D. Levitt & Stephen J. Dubner. Levitt, Steven D. Dubner, Stephen J. Economics Psychological aspects. Economics Sociological aspects. 330 LEF Includes bibliographical references and index. New York : Harper Perennial, c2009. c2009. 2009 Text xxvi, 315 p. ; eng