From Scott Lindholm at Beyond the Box Score on March 17, 2014:
Pythagorean Wins (PW) is a concept invented by Bill James which numerically states the obvious–teams that score more runs than their opponents typically win more games. This is the formula:
Runs Scored ^ 2 / ((Runs Scored ^ 2) + (Runs Allowed ^ 2))
It’s a retrospective formula in that it can only describe what already occurred, but it still has value. It’s common to relegate major differences between the formula and actual records to “luck.” For example, if a team wins nine games by one run and loses the tenth 10-1, the PW formula would suggest a .500 record instead of the actual 9-1 performance. This is an extreme example but describes some of the variability involved.
Can PW be used to evaluate managerial effectiveness?
Read the full article here: http://www.beyondtheboxscore.com/2014/3/17/5504652/manager-pythagorean-wins
Originally published: March 17, 2014. Last Updated: March 17, 2014.