If you are going to use some set of risk-reward measures (such as Sharpe Ratio) to judge investment performance, you need to keep your eyes on the prize: The overall performance of your portfolio, not that of the individual portfolio components.
We show how manager diversification improves confidence in predicting future hedge fund returns and can be used as a substitute for demanding long track records.
I review “Multi-Dimensional Diversification” by Dr. Rufus G Rankin. It’s a quick, jargon-free introduction to using principal component analysis as a route to creating a more diverse asset portfolio. Highly recommended.