AQR, manager of $200bb+ fund is on the cover of Bloomberg Businessweek this month with an in-depth defence of their factor-driven investing approach.  It’s newsworthy because their main fund has declined 14% this year amid a rising market for its worst underperformance in its history. A lot of “value investors” believe in buying statistically “cheap” companies that have lower P/E, P/B or EV/EBITDA for example vs the market. But what if the world has changed?  What if the backwards looking financial numbers are no longer as predictive as they once...