The last post focused on WAR at a league level. Now I want to see how accurately WAR works at a team level. This post will focus on team strength with respect to batting for the 2013 season. The next post will look at WAR pitching results at a team level.
Each team accumulates runs scored and runs scored against. Teams who score more runs than they let up in general win more ball games. Runs scored are the responsibility of batters; runs scored against the responsibility of pitchers and perhaps fielders. For now let’s just assume pitchers.
The following two formulae define the first two columns of the below table. They represent team strength for BATters and PITCHers. For the year 2013 the league team average for both runs scored and runs scored against was 674. The below table lists the top 6 teams sorted by the best batting. The full 30 team table can be found on a separate page for reference here.
BAT(RAA) = R(Team) – R(League Team Average)
PITCH(RAA) = RA(Team) – R(League Team Average)
Update: The above formula for PITCH(RAA) was backwards. I originally posted it here but won’t bother to change it there. Below is the correct formula — it was just reversed. The below formula has been used throughout in the code that makes these tables so that has always been correct.
PITCH(RAA) =R(League Team Average) – RA(Team)
Notice the top three teams did very well in post season. The UR column stands for Unearned Runs above average. The Runs Against component has two types; earned and unearned. The average number of unearned runs per team in 2013 was 50. A team like Baltimore with a +19.1 UR means they gave up fewer than average unearned runs or 50-19=31. One could conclude that as a team Baltimore had good fielding.
Clearly there is a problem with team level batting WAR. The Dodgers and Pirates both produced less than the league average of 674 runs per team yet WAR has them ranked #2 and #3 amongst all MLB teams. Since WAR incorporates fielding in with their batting ratings perhaps that had an effect. Perusing the UR column the Dodgers let up 8 more unearned runs than the league average of 50/team. Logically their fielding was worse than average so what made WAR rank them so highly in the batter category? Pittsburgh weighs in slightly above average with respect to unearned runs but they were 40 runs below the league average runs produced.
The above table shows the WAR ranking of 4 of the top 6 teams in the first table using the simple runs above average calculation. St. Louis comes in as #19 out of 30 teams meaning WAR thinks St. Louis was in the bottom tier of MLB teams with respect to batting. All four teams above gave up less unearned runs than average according to the UR column.
The above tables clearly show a problem with WAR at the team level with respect to batting. The next post will cover pitching.