Baseball Hacks

Measure Fielding with Fielding Percentage

Measure how well a defensive player performed with fielding percentage.

Fielding percentage is a very simple measurement. It measures the number of successfully fielded balls (putouts and assists) divided by the number of opportunities (putouts, assists, and errors).

Sabermetric types don’t like this measurement, for several reasons. First, it is somewhat subjective. Fielding percentage only counts errors as missed opportunities, and the official scorer decides errors. Second, errors are rare compared to putouts and assists. Fielding percentages are very high for most major league players, more than 98% on average. Third, fielding percentage misses a lot of subtlety. It doesn’t include badly fielded plays such as ground balls missed by infielders, and great plays such as fly balls caught just over the fence to prevent home runs.

Finally, fielding percentage penalizes players who try to make good plays and fail. If a player can’t even make it to a ball, he can’t get an error. This is important: slow infielders or outfielders might end up nowhere near the ball, so they don’t mess up fielding the ball or catching it as often as do players with better range. (Hence the reason for this statistic: range factor.) This is the principal objection to Derek Jeter as a fielder: just because he doesn’t get a lot of errors doesn’t mean he’s a good shortstop. He has poor range.

Fielding percentage has one thing going for it: it’s easy to calculate. Let’s ...