by Roger Ibbotson
Classical and behavioral finance are often seen as being at odds, but the idea of “popularity” has been introduced as a way of reconciling the two approaches. Investors like or dislike various characteristics of securities for rational reasons (as in classical finance) or irrational reasons (as in behavioral finance), which makes the assets popular or unpopular. In the capital markets, popular (unpopular) securities trade at prices that are higher (lower) than they would be otherwise; hence, the shares may provide lower (higher) expected returns.This book builds on this idea and expands it in two major ways.