Tirole (1982) is commonly interpreted as proving that bubbles are impossible with finitely many rational traders with common priors. We study a simple variation of his model in which bubbles can occur, even though traders have common priors and common knowledge that the asset has no fundamental...

Tirole (1982) is commonly interpreted as proving that bubbles are impossible with finitely many rational traders with common priors. We study a simple variation of his model in which bubbles can occur, even though traders have common priors and even though it is common knowledge that the asset...

This article integrates strategic product market analysis with price-taking asset pricing theory. We demonstrate that a firm's market power can lead to scale-dependent and potentially infinite required returns. Scale dependency, which we relate to risk spillovers between expansionary and...

We develop a model of trading by an informed fund manager compensated on the basis of her fund's Net Asset Value (NAV). We show that she has an incentive to pump her portfolio by buying securities she already holds. Pumping leads to excessive trading and hurts long-term fund performance. It also...

Horizontal mergers exert price pressure on dependent suppliers and adversely affect their performance. Consistent with the theory of countervailing power, concentrated suppliers and those with greater barriers to entry experience larger price declines after consolidation downstream. Time-series...