Aside from the equilibrium that Hotelling (1931) displayed, his model of non-renewable resources also contains a continuum of bubble equilibria. In all the equilibria the price of the resource rises at the rate of interest. In a bubble equilibrium, however, the consumption of the resource peters...

We apply and extend the cost-based approach to bundling and tying under competition developed in Evans and Salinger (2004) to over-the-counter pain relievers and cold medicines. We document that consumers pay much less for tablets with multiple ingredients than they would if they bought tablets...