Many studies have documented large and persistent productivity differences across producers, even within narrowly defined industries. This paper both extends and departs from the past literature, which focused on technological explanations for these differences, by proposing that demand-side...

The North Dakota Railroad War of 1905, which pitted a potential entrant (the Soo Line) against an established monopolist incumbent (the Great Northern Railway), offers a lucid empirical example of strategic behavior, and in particular the potential for entry deterrence through product...