have recently demonstrated that the method typically used to form portfolios in stock market studies results in the returns of small-firm portfolios being overstated.
correctly, measuring the risk and return of small-firm portfolios appears to eliminate at least 50% of the small-firm effect
has document that over half of the small-firm effect occurs in January and most of the abnormal return associated with January takes place during the first 5 days of trading
argue that a large portion of the small-firm effect can be explained by the fact that transaction cost are higher for small firms