... to allow for firm heterogeneity and Mazzeo (2002) and Seim (2006) extended the analysis and estimation of entrygames to allow for product differentiation. Davis (2006c) allowed for some forms of ... jurisdictions.4See, for example, the work by Sutton (1991), Klepper (1996), and Klepper and Simons (2000), and in the strategy literature see Markides and Geroski (2005) and McGahan (2004).6.1. ... unobserved and observed firm heterogeneity in profitability, for example, in terms of different costs, and therefore any model should account for itappropriately. Many if not all firms, agencies, and...