> Current research from AQR seems to suggest that HmL isn't actually a persistent factor [...] Also current research by AQR suggests that that value is more str

> Current research from AQR seems to suggest that HmL isn't actually a persistent factor [...] Also current research by AQR suggests that that value is more structural, and is a real risk premia. I'm lost. HmL is the classic "value" factor (as in the 3-factor model of Fama and French: market, size and value). I don't say that's the best definition possible (clearly it's not) and I know other definitions exist (but HmL has the advantage of being available for a century). For what it's worth, I prefer cash-flow-based metrics and total shareholder yield (dividends + buybacks + debt reduction). AQR use an improved definition (using data as current as possible) but I don't think it's terribly different: "The bottom line is that while the standard approach to value was a reasonable and conservative choice that has served the field well, it is not the best possible choice." https://www.aqr.com/Insights/Research/Journal-Article/The-Devil-in-HMLs-Details https://www.aqr.com/Insights/Research/Journal-Article/The-De... In their latest publication ("Factor Premia and Factor Timing: A Century of Evidence", that I've not yet read) they say: "We follow simple value measures used in the literature to capture “cheap” versus “expensive” securities within an asset class. For individual equities, we use the book-to-market ratio following Fama and French (1992, 2012) and Asness, Moskowitz, and Pedersen (2013). For global equity indices, we use the aggregate 10-year cyclically-adjusted price-to-earnings ratio CAPE (value-weighted average P/E ratio for all constituent firms in the index)."