When False Factors Are Exposed
The world of finance and asset pricing used to be fairly simple. At first, there was just the single-factor capital asset pricing model, with market risk (beta) as the sole factor to explain the differences in returns of diversified portfolios. Over time, the working model evolved into a still relatively simple four-factor model, adding value, size and momentum. Each of these four factors carried large premiums.
However, as John Cochrane put it, today we have a literal factor zoo, with more than 600 factors having been identified in the literature (roughly 300 of which have been identified in top journal articles and highly regarded working papers).
Read the rest of the article on ETF.com.