In a provocative paper, Santa-Clara and Valkanov (2003) present evidence that stock market returns are much higher under Democratic presidents than Republican presidents. Their work was updated by Pastor and Veronesi (2017), who find that the effect is even stronger when the data are extended...

In our paper — “How Can ‘Smart Beta' Go Horribly Wrong?” — we show, using U.S. data, that the relative valuation of a strategy (in comparison with its own historical norms) is correlated with the strategy's subsequent return at a five-year horizon. The high past performance of many of...