That women of lose more than expected when they play against men of equivalent rating is entirely consistent with regression towards the mean [1]. Because elo

That women of lose more than expected when they play against men of equivalent rating is entirely consistent with regression towards the mean [1]. Because elo ratings contain error and men are on average better at chess [2], the average true value that elo ratings are trying to measure will be lower for women than men at equivalent elo ratings. [1] http://en.wikipedia.org/wiki/Regression_toward_the_mean http://en.wikipedia.org/wiki/Regression_toward_the_mean [2] About 1 SD, http://rspb.royalsocietypublishing.org/content/277/1692/2269.full http://rspb.royalsocietypublishing.org/content/277/1692/2269...