Batted Ball Data (GB%, LD%, FB%)
Description:
The meanings of these terms are fairly evident; they represent a ratio of batted-ball type to total balls in play. Unlike BABIP, though, the Balls in Play figures used for these statistics factor in balls that leave the park (Home Runs). As such, when adding the three figures you will get the entirety of balls in play (100%). Major league ballplayers have a variety of swings that result in a variety of batted ball demographics; these result in a wide array of “true talent-levels” in the way players put the ball in play. We haven’t included in-field flies (or pop-ups) because they don’t seem to be any sort of true-talent (i.e. they don’t correlate year over year as well as the others).
Context:
League Average Rates (2005-2009):
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GB%: 45%
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FB%: 36%
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LD%: 19%
Some extremes (from the last 3 years combined):
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Carlos Pena: 49.4 FB%, 17.6 LD%, 33 GB%
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Luis Castillo: 18.5 FB%, 17.9 LD%, 63.6 GB%
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David Wright: 37.3 FB%, 24.8 LD%, 37.9 GB%
A sampling of 2009 Rays:
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Evan Longoria: 41.8 FB%, 19.1 LD%, 39.1 GB%
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Ben Zobrist: 38.5 FB%, 20.0 LD%, 41.5 GB%
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Jason Bartlett: 39.1 FB%, 26.0 LD%, 35.0 GB%
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B.J. Upton: 40.3 FB%, 15.4 LD%, 44.3 GB%
Things to Remember:
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Line drives are the best.
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The expected run value for a LD is .384. Contrast that to a GB (.04) and a FB (.1).
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The expected out value for a LD is .305. Contrast that to a GB (.8) and a FB (.79).
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In other words, a LD produces 1.26 runs/out while GBs produce .05 R/O and FBs produce .13 R/O.
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Line drive rates generally group around the average with less deviation. Groundball and flyball rates are more prone to fluctuate from hitter to hitter.
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Players that sacrifice balls in the air (higher GB with lower FB and LD) generally have higher BABIPs, but they sacrifice a lot in slugging.
Links for Further Reading:
BABIP: Slicing and Dicing Groundball Out Rates – Baseball Analysts
