FantasyPros has put together a glossary of sabermetrics statistics for readers to reference. Deeper statistical analysis is being used by fantasy players more and more in daily and season-long leagues. We’re providing the glossary so that you can easily reference what the stats we use in our articles refer to and how they should be used for fantasy baseball purposes. Below we’ll start by looking at LD%/GB%/FB%.
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LD%/GB%/FB% make up batted ball stats. Individually, they stand for line drive percentage, groundball percentage, and fly ball percentage. These stats express the amount of balls put into play as ground balls, line drives, or fly balls. The sum of all three percentages will equal 100%. The stats are calculated simply by dividing each category of batted ball by the total number of balls put into play.
Line Drives/Balls in play = LD%
Ground Balls/Balls in Play = GB%
Fly Balls/Balls in play = FB%
These batted ball stats can be used to determine into what category a hitter or pitcher falls. Anything above or below the league average spotlights the player’s tendencies. The league average rates for balls in play are as follows:
Line Drive = 20%
Ground Ball = 45%
Fly Ball = 35%
Because regular counting stats (HR, RBI, extra base hits, etc.) don’t tell the whole story, using these batted ball rates will give a better understanding of exactly what type of hitter a particular player may be. For example, a batter can find himself unlucky with the number of home runs hit, but if his fly ball rate is over 45%, the home runs and extra-base hits are bound to come. In 2014, Chris Carter of the Houston Astros led all MLB players with a 51.4% FB% and also finished tied for second in the majors with 37 home runs. Another example is Mike Trout who led all players in total bases (338) and had an above average FB% (47.2%). Players who hit more fly balls naturally hit more home runs.
On the flip side, if a batter hits over 20 home runs but is carrying a ground ball rate over 50% and a fly ball rate below average, there is a good amount of luck involved and the batter is bound to return to lower home run totals. A prime example is Robinson Cano. A career 48.4% GB% and 30.2% FB% told many that the yearly 25-plus home runs he was hitting from 2009-13 was a condition of playing in the new Yankee Stadium and not indicative of a power hitter. Since signing with Seattle and moving away from New York in 2014, the numbers have fallen back to expectations. Cano has hit only 15 home runs in over 750 at-bats.
Since line drives fall in for base hits approximately 75% of the time, a higher than average line drive rate correlates well with an increased batting average. High average hitters, such as Joey Votto and Joe Mauer, find themselves at the top of the LD% ranks as well.
We use batted ball stats to define a pitcher’s profile and sort them as either a ground ball or fly ball pitcher. A pitcher with a GB% of over 50% would be classified as a ground ball pitcher. While a player with close to or above 45% FB% is a fly ball pitcher. This is important to know since pitchers do not have complete control over what happens to a baseball once it has been put into play. However, a pitcher may affect what type of batted ball is allowed into play. If a pitcher allows mainly ground balls, he limits how many of the batted balls reach the seats and batters will be held, primarily, to singles. On the other hand, fly ball pitchers can limit the number of base hits they allow, but that also leaves them more vulnerable to home runs.
Determining which type of pitcher a player is will help savvy fantasy owners make tough lineup decisions and give them an edge over the casual fantasy player. In some of the more hitter-friendly parks (i.e., Yankee Stadium, Coors Field) a ground ball pitcher would be preferred since home runs will be limited. While in some of the more spacious stadiums where the ball does not carry (i.e., Safeco Field, PetCo Park), fly ball pitchers can do just fine, if not better, than ground ball pitchers.
Dale Redman is a correspondent at FantasyPros. To read more from Dale, check out his archive and follow him @fantasytool.
