We investigate how liability rules and property rules affect the incentives to invest in research tools. We argue that it is hard to deter infringement under any of the enforcement regimes available. However, counterintuitively, a credible threat of infringement can actually be beneficial to the...

Incorporating space in economic models has two important consequences. First, the hypothesis of perfect competition becomes untenable, and second, the distinction between private and public goods becomes blurred. We review arguments that lead to these conclusions and summarize recent work...