I develop a model of (individually rational) collective reality denial in groups, organizations and markets. Whether participants' tendencies toward wishful thinking reinforce or dampen each other is shown to hinge on a simple and novel mechanism. When an agent can expect to benefit from other's...

We develop a model of financially constrained arbitrage, and use it to study the dynamics of arbitrage capital, liquidity, and asset prices. Arbitrageurs exploit price discrepancies between assets traded in segmented markets, and in doing so provide liquidity to investors. A collateral...

We consider a moral hazard setup wherein leveraged firms have incentives to take on excessive risks and are thus rationed when they attempt to borrow in order to meet liquidity shocks. The rationed firms can optimally pledge cash as collateral to borrow more, but in the process must liquidate...

The paper studies the causes of the current financial crisis and considers proposals for mitigation and prevention of future crises. The crisis is was the product of a ‘perfect storm’ bringing together a number of microeconomic and macroeconomic pathologies. Among the microeconomic systemic...

We study the effect of frequent trading opportunities and categorization on pricing of a risky asset. Frequent opportunities to trade can lead to large distortions in prices if some agents forecast future prices using a simplified model of the world that fails to distinguish between some states....

A Capital Asset Pricing Model of a stock market economy is examined under different corporate governance structures in which the objectives of managers and entrepreneurs in choosing the risk composition of their firms' returns are not aligned with those of shareholders and investors because of...

We study a model where some investors (“hedgers”) are bad at information processing, while others (“speculators”) have superior information-processing ability and trade purely to exploit it. The disclosure of financial information induces a trade externality: if speculators refrain from...

New evidence suggests that individuals "learn from experience," meaning they learn from events occurring during their own lifetimes as opposed to the entire history of events. Moreover, they weigh more heavily the more recent events compared to events occurring in the more distant past. This...

Under rational expectations monetary policy is generally highly effective in stabilizing the economy. Aggregate demand management operates through the expectations hypothesis of the term structure --- anticipated movements in future short-term interest rates control current demand. This paper...

Agents have two forecasting models, one consistent with the unique rational expectations equilibrium, another that assumes a time-varying parameter structure. When agents use Bayesian updating to choose between models in a self-referential system, we find that learning dynamics lead to selection...