A Note on Trader Sharpe Ratios

A Note on Trader Sharpe Ratios

Traders in the financial world are assessed by the amount of money they make and, increasingly, by the amount of money they make per unit of risk taken, a measure known as the Sharpe Ratio. Little is known about the average Sharpe Ratio among traders, but the Efficient Market Hypothesis suggests that traders, like asset managers, should not outperform the broad market. Here we report the findin...

The Statistics of Sharpe Ratios

The building blocks of the Sharpe ratio—expected returns and volatilities— are unknown quantities that must be estimated statistically and are, therefore, subject to estimation error. This raises the natural question: How accurately are Sharpe ratios measured? To address this question, I derive explicit expressions for the statistical distribution of the Sharpe ratio using standard asymptotic t...

Sharpe Ratio Practice Note

A Note on the Dynamics of Target Leverage Ratios

In this communication we have proposed a simple model for the dynamics of the target leverage ratio of a rm and performed a theoretical investigation of its time path. The gap between a rm’s current target leverage ratio and the long-term target ratio is found to diminish exponentially, and the decay rate is determined by the volatility of the leverage ratio and the long-term target ratio only....

A Note on “predicting Returns with Financial Ratios”

This note reinterprets methods that seek to use the aggregate dividend price ratio to predict aggregate stock market returns; specifically, methods which use information about time-varying changes in the dividend-price ratio process to improve the prediction equation. It argues that the empirical evidence is still too weak to suggest practical usefulness of these estimators. ∗We thank John Coch...