The addition of momentum need not boost turnover relative to a value investing strategy, and therefore, need not incur the high trading
costs of a momentum strategy.
Third, based on this result, we investigate whether there exist capacity constraints in time - series momentum strategies, by running predictive regressions
of momentum strategy performance on lagged capital flows into the CTA industry.
Years of suppressed volatility and the
success of momentum strategies — betting on yesterday's winners rising even further — have led many investors to pile into similar investments, as the chart below shows.
«An important
advantage of momentum strategies is that they may provide downside protection during sharp market corrections, while maintaining upside participation during bull markets... Undoubtedly, these strategies also experience periods of subpar performance.
The obvious way to combine strategies is to use leverage: for example, to reduce the market
risk of a momentum strategy as much as possible, to do the same thing with a value strategy, and then to borrow money at a low rate in order to get exposure to both.
Momentum is one of the most compelling factors in theoretical long — short paper portfolios, but live
results of momentum strategies fall short of theoretical returns.
For example, Frazzini, Israel, and Moskowitz (2012) analyze trading costs associated with an actual implementation
of a momentum strategy by an active manager.
Thus, the implementation capabilities of an active
manager of a momentum strategy should be reviewed just as rigorously as, if not more so, the manager's trading expertise.
When the factor is momentum, this phenomenon is aggravated by the fact that, in order to squeeze the highest performance
out of a momentum strategy, turnover of close to 100 % a month is required.
Other researchers, including Novy - Marx and Velikov (2014) and Hsu et al. (forthcoming), have estimated the trading costs associated with index - like
implementation of a momentum strategy.