Jesper B. S\u00f8rensen and Olav Sorenson<\/strong><\/p>\n Studies consistently find regions dense in concentrations of similar firms to be fecund sources of new firms of the same kind. This pattern persists even in industries with negative returns to geographic concentration. Why do these patterns persist? On the one hand, social networks may constrain entrepreneurs’ opportunities, making it difficult to mobilize resources in more attractive locations. On the other hand, nascent entrepreneurs may systematically misperceive opportunities in such a way as to lead them to continue founding attempts in overcrowded regions. To distinguish between these two processes, we analyze a unique set of data on television stations that contains information on both attempts to start new stations, as well as successful foundings. Our exploratory analysis suggests that nascent entrepreneurs do consistently misinterpret information related to population dynamics. These patterns could easily contribute both to industrial agglomeration and to the fragility of Red Queen dynamics. We discuss the implications of these results for both future research and for public policy.<\/p>\n