Equity style timing

Christopherson and Williams (1997) define an equity style as an investment belief held by a group of managers who believe that following it will add value. They further state that to be valid, a style should result in the clustering of factor tilts or portfolio characteristics among those portfolios that share the style, and furthermore have a broad following among investors. If only one firm holds a philosophical belief, it is more appropriate to refer to the belief as an "investment insight" that belongs to that firm alone.