A Comment on “Better Beta Explained: Demystifying
Alternative Equity Index Strategies”

Abstract

Cap-weighted indices have been subjected to increasing criticism. Empirical evidence suggests that cap-weighted indices deliver poor risk-adjusted performance. It has also been questioned whether market cap is a reliable proxy for the size and economic influence of a company. The fact that cap-weighted indices have been found to be neither representative nor efficient has led to the development of various alternative weighting schemes. However, how to best replace cap-weighted indices remains an open question. In an article from the Summer 2011 issue of The Journal of Index Investing, Robert Arnott discusses an empirical analysis of several alternative indexing methodologies that he broadly classifies as relying on heuristics or on portfolio optimization. Although an analysis of competing non-capweighted indices should, in principle, provide useful insights, the results reported by Arnott suffer from a flawed methodology and may confuse readers about the issues with different non-cap-weighted indices in practice.