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MLB Hall of Fame - Lesson 02 - Advanced Batter Stats

Jonathan Bales is the author of Fantasy Baseball for Smart People—a 197-page book created to help you win playing daily fantasy baseball on DraftKings. Predicting hitter performances on a day-to-day basis is a tough business. Whereas pitcher production is fairly consistent from start to start, hitter…

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Jonathan Bales is the author of Fantasy Baseball for Smart People—a 197-page book created to help you win playing daily fantasy baseball on DraftKings.

Predicting hitter performances on a day-to-day basis is a tough business. Whereas pitcher production is fairly consistent from start to start, hitter production is volatile; even in a dream matchup, a batter than go 0-for-5 with three Ks.

That doesn’t mean that stats are useless in daily fantasy baseball, however. On the contrary, because there’s a decent amount of randomness in results on the daily level, it means we should place even more emphasis on long-term data. Jose Bautista might hit three home runs in a game or he might strike out four times—there’s a wide range of outcomes for every batter in every game—but the most likely outcome is that he hits near his mean.

Our job is to determine what that “mean” is. Is it a player’s career average in a particular area? Is it a totally random stat for which we should be using a league mean? That’s where advanced stats come into play. They’re numbers that are representative not of what has happened in the past—as is the case with something like batting average—but rather, representative of what’s most likely to occur in the future.

Here’s a look at a few of my favorite advanced stats to consider for batters.


Weighted On-Base Average (wOBA) is a stat that has gained more and more acceptance in the daily fantasy and general baseball communities. Invented by Tom Tango—author of The Book—it seeks to adjust batting average relative to how important certain types of hits actually are for an offense. Whereas batting average values a home run the same as a single, for example, wOBA weights each type of hit according to how much it actually helps an offense.

wOBA is therefore a catch-all statistic that tries to capture a hitter’s entire value at the plate. I use wOBA to help find value among hitters, specifically when wOBA deviates wildly from batting average or on-base percentage. If a batter has a low batting average but a decent wOBA, he might end up being underpriced.

wOBA is especially useful when selecting batters for your cash-game lineups. Because cash games are generally about point-maximization, a stat that shows a hitter’s overall worth to his team—and is a good proxy for his overall fantasy value—is useful.


OPS+ is a version of OPS (On-Base Percentage Plus Slugging Percentage) that adjusts for variables like ballpark factors. OPS+ is a slightly better version of OPS.

In real life, wOBA is a better stat than OPS+ because wOBA weights hits according to their actual worth. OPS+, however, does a nice job of capturing a hitter’s power, and power is important in daily fantasy baseball. Home runs are worth so much on DraftKings, so it makes sense to give a little extra weight to the hitters who can consistently go deep. If a hitter can’t hit a home run or steal a bag with regularity, I’m very unlikely to roster him, particularly in tournaments.

I use OPS+ and ISO (Isolated Power) to help determine how likely a batter is to go deep.


Home runs per fly ball (HR/FB) is a stat that helps to determine how lucky a batter has been in the past. HR/FB is more standardized for pitchers because they face a variety of different batters over the course of a season, so individual HR/FB rates even out. While there’s a lot of regression toward the mean in HR/FB for hitters, too, there are also differences in how likely a hitter is to have a fly ball leave the park.

That means that we can’t compare a hitter’s HR/FB to the league mean because Player X might be twice as likely as Player Y to see a fly ball turn into a home run, even over the long run.

Even so, I like to use a hitter’s recent HR/FB rate to determine how lucky he’s been of late by comparing it to his career rate. If a batter who normally hits a home run every 15 fly balls has six homers over his past 20 fly balls, that’s a sign that he’s probably been a bit lucky. He might be swinging the bat well, but there’s no way he’s going to keep up that pace. If he’s priced as though he will, that’s a situation to avoid, even if the batter has been crushing it.

HR/FB is similar to Batting Average on Balls In Play in that we’re trying to decipher the amount of luck inherent to recent results, though HR/FB overall isn’t as affected by randomness as BABIP.

Batted Ball Profile

A player’s batted ball profile is the percentage of his batted balls that are ground balls, line drives, and fly balls. Obviously, more line drives is better.

Line drives are the least common type of batted ball, however, so what you should really be trying to target in your hitters is fly balls. Whereas ground balls rarely lead to extra-base hits, fly balls can leave the park and give your daily fantasy roster a lot of upside.

Further, Major League Baseball has seen a recent shift to more and more ground ball pitchers. Teams have noticed how detrimental ground balls are to offenses, and have thus targeted more pitchers who can produce a lot of them. Well, the type of hitter that’s most likely to take advantage of ground ball pitchers is one who naturally hits the ball into the air. A ground ball hitter versus a ground ball pitcher is a death blow for an offense.


I’ve mentioned this on numerous occasions in this daily fantasy baseball series, but it’s vital for you to break down every stat possible into lefty/righty splits. Many batters hit wildly different versus lefties than against righties, so it would be a mistake to treat the two in the same way.

One thing I look for is a hitter who has large splits—excelling versus one handedness and struggling against the other. The reason I do that is because it often leads to value in daily fantasy baseball. If DraftKings is pricing a batter according to his overall numbers, for example, he’ll frequently be underpriced when he faces the handedness against whom he excels. Meanwhile, he’ll be overpriced against the handedness that gives him trouble. It just comes down to recognizing how a player is priced and when he’s in a situation that’s superior to what his salary suggests, which often happens with players who have a large deviation in their splits.

Stolen Bases

Finally, I want to mention that one of the overlooked aspects of fantasy baseball batter value is the ability to steal bases. Stolen bases are difficult to predict on the nightly level, but the same players continually steal bags, so if you’re emphasizing them on a consistent basis, you’ll eventually get them.

One of the reasons that steals are undervalued, in addition to being difficult to predict, is that they aren’t factored into most advanced statistics. Even wOBA doesn’t account for stolen base upside, so a batter who can swipe bags can really provide a lot of value. There’s a good chance that stolen base upside isn’t factored into daily fantasy baseball salaries as heavily as it should be.

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Continue Reading MLB Training Camp

MLB Hall of Fame – Lesson 01 – Advanced Pitching Stats
MLB Hall of Fame – Lesson 02 – Advanced Batting Stats
NEXT LESSON – MLB Hall of Fame – Lesson 03 – Stacking Strategy
MLB Hall of Fame – Lesson 04 – Value of Stolen Bases

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