Records of over half a million participants in more than 600 401(k) plans indicate that participants tend to allocate their contributions evenly across the funds they use, with the tendency weakening with the number of funds used. The number of funds used, typically between three and four, is...

Although established money managers operate in an environment which seems competitive, they also seem to be very profitable. The present value of the expected future profits from managing a collection of funds is equal to the value of the assets under management multiplied by the profit margin,...

Focusing on capital asset returns governed by a factor structure, the Arbitrage Pricing Theory (APT) is a one-period model, in which preclusion of arbitrage over static portfolios of these assets leads to a linear relation between the expected return and its covariance with the factors. The APT,...

Building on recent developments in behavioral asset pricing, we develop a model in which an increase in the dispersion of investor beliefs under short-selling constraints predicts a "bubble," or a rise in a stock's price above its fundamental value. Our model predicts that managers respond to...

We present a model of the maturity of a bank’s uninsured debt. The bank borrows funds and chooses afterwards the riskiness of its assets. This moral hazard problem leads to an excessive level of risk. Short-term debt may have a disciplining effect on the bank’s risk-shifting incentives, but...

Shortfall aversion reflects the higher utility loss of a spending cut from a reference point than the utility gain from a similar spending increase, in the spirit of Prospect Theory's loss aversion. This paper posits a model of utility of spending scaled by a function of past peak spending,...

We present a model of the maturity of a bank's uninsured debt. The bank borrows funds and chooses afterwards the riskiness of its assets. This moral hazard problem leads to an excessive level of risk. Short-term debt may have a disciplining effect on the bank's risk-shifting incentives, but it...

Retail clients at a major German discount broker trade in tandem - they tend to be on the same side of the market in a given stock during a given day, week, month, and quarter. Neither aggregate liquidity effects nor short sale constraints fully explain this behavior. The systematic execution of...