In a capitalist economy prices serve to equilibrate supply and demand for goods and services, continually changing to reallocate resources to their most efficient uses. However, secondary stock market prices, often viewed as the most 'informationally efficient' prices in the economy, have no...

The dynamic behavior of security prices is studied in a setting where two agents trade strategically and learn over time from market prices. The model introduces an information structure which is intended to capture the notion that information is difficult to interpret. Strategic interaction and...

In efficient markets the price should reflect the arrival of private information. The mechanism by which this is accomplished is arbitrage. A privately informed trader will engage in costly arbitrage, that is, trade on his knowledge that the price of an asset is different from the fundamental...

This paper presents a simple general equilibrium model of asset pricing in which profitable informed trading can occur without any "noise" added to the model. It shows that models of profitable informed trading must restrict the portfolio choices of uninformed traders: in particular, they cannot...

Noise traders are agents whose theoretical existence has been hypothesized as a way of solving certain fundamental problems in Financial Economics. We briefly review the literature on noise traders. The is an entry for The New Palgrave: A Dictionary of Economics, 2nd Edition (Palgrave Macmillan:...

We consider a model of the stock market with delegated portfolio management. All agents are rational: some trade for hedging reasons, some investors optimally contract with portfolio managers who may have stock-picking abilities, and portfolio managers trade optimally given the incentives...

Systemic risk arises when shocks lead to states where a disruption in financial intermediation adversely affects the economy and feeds back into further disrupting financial intermediation. We present a macroeconomic model with a financial intermediary sector subject to an equity capital...

The Flow of Funds table on federal funds and security repurchase agreements reports and attempts to balance the net lending/borrowing positions of various types of financial institutions. Prior to 2008, this table shows a huge unallocated discrepancy in the form of missing lending (i.e., reverse...

"Limits of Arbitrage" theories hypothesize that the marginal investor in a particular asset market is a specialized arbitrageur rather than a diversified representative investor. We examine the mortgage-backed securities (MBS) market in this light. We show that the risk of homeowner prepayment,...

We present a model of optimal intervention in a flight to quality episode. The reason for intervention stems from a collective bias in agents' expectations. Agents in the model make risk management decisions with incomplete knowledge. They understand their own shocks, but are uncertain of how...