Interest in prediction markets has increased in the last decade, driven in part by the hope that these markets will prove to be valuable tools in forecasting, decision-making and risk management - in both the public and private sectors. This paper outlines five open questions in the literature,...

We develop a model of the gambler's fallacy -- the mistaken belief that random sequences should exhibit systematic reversals. We show that an individual who holds this belief and observes a sequence of signals can exaggerate the magnitude of changes in an underlying state but underestimate their...

How does the trading behaviour of institutional money managers affect stock prices? In this paper we document a robust relationship between the net trade patterns of institutional money managers and long term equity returns. Examining quarterly data on US institutional holdings from 1983 to...

We propose a rational theory of momentum and reversal based on delegated portfolio management. A competitive investor can invest through an index fund or an active fund run by a manager with unknown ability. Following a negative cashflow shock to assets held by the active fund, the investor...

We propose a model in which assets with identical cash flows can trade at different prices. Infinitely-lived agents can establish long positions in a search spot market, or short positions by first borrowing an asset in a search repo market. We show that short-sellers can endogenously...

We examine how liquidity and asset prices are affected by the following market imperfections: asymmetric information, participation costs, transaction costs, leverage constraints, non-competitive behavior and search. Our model has three periods: agents are identical in the first, become...

This paper compares the behavior of Euro-Area (EA) banks’ credit and reserves with those of US banks following respective major crisis triggers (Lehman’s collapse in the US and the 2009 admission by Papandreou, that Greece’s deficit was substantially higher than previously believed, in the...

We combine self-collected historical data from 1867 to 1907 with CRSP data from 1926 to 2012, to examine over 140 years of risk and return of one of the most popular mechanical trading strategies—momentum. We find that the momentum strategy has earned abnormally high risk-adjusted returns—a...

We show that the stock market may fail to aggregate information even if it appears to be efficient and that the resulting decrease in the information content of stock prices may drastically reduce welfare. We solve a macroeconomic model in which information about fundamentals is dispersed and...

This lecture is about how best to evaluate economic theories in macroeconomics and finance, and the lessons that can be learned from the past use and misuse of evidence. It is argued that all macro/finance models are `false' so should not be judged solely on the realism of their assumptions. The...