In Part I of this series, we explored Grinold’s Fundamental Law of Active Management, and why the theory leads to misguided conclusions in the presence of asset correlations. In this article we will offer a primer on a useful tool for portfolio evaluation, Principal Component Analysis (PCA), and illustrate how PCA can help quantify the number of independent bets in a portfolio of correlated assets.
Grinold linked investment alpha and Information Ratio to the breadth of independent active bets in an investment universe with his Fundamental Law of Active Management. Breadth is often misinterpreted as the number of eligible securities in a manager’s investment universe, but this ignores the impact of correlation.
In this article, we would like to integrate the cluster concepts we introduced in our article on Robust Risk Parity with some ideas proposed and explored by Varadi and Kapler in the last few months
ReSolve Asset Management Blog is an investment research forum, opinion pieces, and educational material from the team at ReSolve Asset Management. Our views are driven by evidence based finance, with a special focus on asset allocation, factors and smart beta, retirement and endowment strategies, and quantitative methods.
