When should we expect bubbles? Can levered intermediaries bid up risky asset prices through asset substitution? We study an economy with financial intermediaries that issue debt and equity to buy risky assets. Asset substitution alone cannot cause bubbles because it is priced into the...

We analyze a dynamic model of informed trading where a shareholder accumulates shares in an anonymous market and then expends costly effort to change the firm value. We find that equilibrium prices are affected by the position accumulated by the shareholder, because the level of effort...

We propose a dynamic asset-market equilibrium model in which (1) an "innovative" asset with as-yet-unknown average payoff is traded, and (2) investors delegate investment to experts. Experts secretly renege on investors' orders and take on leveraged positions in the asset to manipulate...