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Monday, May 14, 2007
Replacement-Level Fielding
How good or bad is the fielding of the bench players compared to the starters? This is what I did:
1. For each season from 2000-2006,
2. Select the 30 players at each position that played the most and classify them as “Starters”
3. Figure out the putouts and assists per 9 inning of the Starters at each position
4. Take the rest of the players and treat them as “Bench”
5. Do the same as #3 for these players
6. Compare
From 2000-2006, the average SS Starter had 2.96 assists per 9 inning game (27 outs), while the Bench SS had 2.92. Here’s how each position group did:
Catcher: Starters, 0.48 assists per game, Bench, same
SS: 2.96, 2.92
2B: 2.93, 2.91
3B: 1.99, 1.93
1B: 0.67, 0.65
Putouts
CF: 2.57, 2.58
RF: 2.05, 2.07
LF: 1.94, 1.95
In short, the typical starting infielder is about +.04 plays per 27 outs (5 runs per 162 GP) better than his backups, while the typical starting outfielder is about -.01 play (1 run per 162 GP) worse than his backups.
For all intents and purposes, the fielding performance of backups are roughly the same as the starters.