The unlucky York Revolution
No, this post has nothing to do with the previous two where one player retired, and another left the team. Rather, it’s about how unlucky the Revolution have been so far this season in regards to run differential.
Noted statistician Bill James, who is essentially the father of Sabermetrics, developed an equation that tells you your “Pythagorean winning percentage.” That is a metric that lets you know how “lucky” or “unlucky” a team is based on the number of runs they’ve scored and allowed in the amount of games they’ve played. This is the equation:
(Runs Scored)^1.83 + (Runs Allowed)^1.83
If you plug in the Revolution’s runs scored as of May 13 (141), and their runs allowed (104) into this equation, it suggests the team should have a .576 winning percentage – which would put York at 13.8 wins out of their first 24 games. Rounding up, based on their Pythagorean winning percentage, the Revs should be 14-10 overall instead of 12-12 based on runs, making them unlucky.
On the other side of the coin, take the Yankees this year, who are a surprise first place team considering their myriad injuries. They’re 23-13 as of May 13, with 157 runs scored and 138 allowed. Those runs plugged into the Pythagorean win-loss metric suggest their record should be 20-16, meaning they are lucky, and three games luckier in the standings than they should be based on runs.
While the Revolution are two games unlucky in the standings, the Yankees are five full games luckier than they are based on runs. Not that comparing across leagues means much, it’s just fun.
I’ll update the Revolution’s Pythagorean winning percentage again throughout the year, and we’ll see if they finish the season with a record that is lucky, unlucky or about right where they should be based on runs scored and allowed. Only 24 games in is too small of a sample size to determine if the team will truly be lucky or unlucky this season, but it’s interesting to keep track of.