A sizable literature has grown up in recent years focusing on two-sided markets in which economies of scale combined with complementarities between a platform and its associated `software' or `services' can generate indirect network effects (that is positive feedback between the number of...

The optimal term of copyright has been a matter for extensive debate over the last decade. Using a simple model we characterise optimal term as a function of a few key parameters. We estimate this function using a combination of new and existing data on recordings and books and find an optimal...

With cumulative innovation and imperfect information about the value of innovations, intellectual property rights can result in hold-up and therefore it may be better not to have them. Extending the basic cumulative innovation model to include `sampling' by second-stage firms, we find that the...

Internet search (or perhaps more accurately `web-search') has grown exponentially over the last decade at an even more rapid rate than the Internet itself. Starting from nothing in the 1990s, today search is a multi-billion dollar business. Search engine providers such as Google and Yahoo! have...

An extensive empirical literature indicates that returns from innovation are appropriated primarily via mechanisms other than formal intellectual property rights -- and that `imitation' is itself a costly activity. However most theory assumes the pure nonrivalry of `ideas' with its implication...

An extensive empirical literature indicates that, even without formal intellectual property rights, innovators enjoy a variety of first-mover advantages and that `imitation' is itself a costly activity. There is also accumulating evidence that an `open' approach to knowledge production can...