Do the Profits from Technical Trading Rules Reflect Inefficiencies?

We investigate whether the demonstrated effectiveness of technical analysis for forecasting equity returns can be reconciled with market efficiency. We find that evidence supportive of technical sell signals identifying periods of negative expected returns is confined to the pre-1940 subsamples. On average, transactions costs eliminate any additional returns to traders using the technical rules. We also demonstrate that technical analysis of an index constructed from CRSP returns, which is not typically observed by practicing technicians, is as useful for forecasting returns as is technical analysis of the widely observed DJIA. Finally, we show that, while technical analysis of individual equity price histories can forecast returns, it does not provide the ability to quot;beat the marketquot;. On balance, we conclude that there is little or no reason to view the evidence of technical forecast power as inconsistent with market efficiency