How should competition law deal with anti-competitive behaviour by firms with market power? In the light of recent EC and US cases, this is perhaps the most controversial current issue for competition policy. Lax policy would jeopardise the competitiveness of markets, but rigid policy would...

We provide a simple necessary and sufficient condition for when a multiproduct demand system can be generated from a discrete choice model with unit demands.

Published as an article in: American Economic Review, 2010, vol. 100, issue 4, pages 1601-15.