David Reibstein is the William Stewart Woodside Professor of Marketing at the Wharton School. The co-founder of Bizrate.com, Reibstein is a marketing expert whose research interests cover marketing ROI, Internet marketing, competitive marketing strategy, market segmentation, marketing models, and understanding brand choice behavior. He has taught at the Harvard Business School and Stanford University, and served as a visiting professor at INSEAD at Fontainebleau, France. An award-winning teacher, Business Week recently named Dave one of the “pick of the B-school crop” of professors.