March 24, 2010
Ahead in the Count
Predicting BABIP, Part 2
In Part One of this series, I updated a model for projecting BABIP, continuing on my previous work from last year. I showed that BABIP can be predicted successfully by looking at batted-ball rates and BABIP on those individual batted-ball types.
Hitters who are able to square up on the ball better will hit more line drives and make more contact in general, so they will have higher BABIPs. Hitters who swing on more of a downward plane will have higher BABIPs, since ground balls are hits more often than outfield fly balls, and those hitters will also hit fewer pop-ups. Similarly, hitters who hit the ball harder in general will have higher BABIPs, and faster players will have higher BABIPs, too, particularly if they hit a lot of ground balls. While many hitters still fall very close to an average range of BABIP, around .300, there are a few hitters who are particularly above average and can be expected to post high BABIPs on a consistent basis for a number of reasons. Last September, I called this group "The BABIP Superstars" and many of these hitters are the same as last year’s group. Next, I will show the top 10 Expected BABIPs for 2010:
Jeter swings on a downward plane that generates a lot of ground balls, while also getting a decent number of line drives. He has ranged between 57-59 percent as far as ground balls in recent years (the league average is 45 percent), and has ranged between 19-22 percent with his line-drive rates (league average is 19 percent). Jeter also rarely pops the ball up, doing so 1.7 percent of the time in 2007, 2.5 percent in 2008, and just 0.7 percent in 2009 (league average is 7.8 percent). Jeter is pretty good at hitting ground balls through the infield, but that skill has regressed somewhat in recent years. He still reaches on infield ground balls at a good rate though, ranging between 13-17 percent (league average is 11 percent). The average rate of hits on outfield fly balls is about .170, while Jeter has ranged anywhere from average to as high as .280 in recent years.
Matt Kemp is one of the few hitters who can put up a high BABIP while not making great contact, striking out in 23 percent and 21 percent of his plate appearances the last two years (where league average is 17 percent). However, when he hits the ball, Kemp hits it very hard. He produced solid line-drive rates, 20 percent and 22 percent the last two years, which obviously helps his BABIP. He also is very good at reaching on infield ground balls, doing so at 16-percent and 22-percent clips the last two seasons (league average is 11 percent). He also rarely pops up (just 1.8 percent and 4.2 percent in 2008-09, below the league average of 7.8 percent), which certainly minimizes the automatic outs. He also does a good job of getting hits to the outfield on fly balls. His outfield fly-ball BABIP was also a solid .216 last year (league average is .170). Kemp also obviously has some home run power, which is indicative of his ability to hit the ball hard enough that it falls in as well.
Like Jeter, Ichiro also has a solid downward swing that produces a lot of ground balls in the hole and minimizes the pop-ups. His ground-ball rate has ranged between 56 percent and 58 percent in recent years, while his pop-ups have remained at between 4.5 percent and 6.5 percent. Ichiro also reaches on infield ground balls at more than twice the league average, doing so in 22 percent, 22 percent and 24 percent of the time the last three years, with a league average of 11 percent. He also makes very good contact, which indicates how well he squares the ball up.
Kendrick was not even on last year’s BABIP Superstars list, but he’s all the way up to fourth this year. Like Jeter and Ichiro, Kendrick also has the downward plane to his swing that generates a lot of ground balls (54 percent, 55 percent, and 55 percent in 2007-09), and very few easy popups (3.2, 2.1, 1.0 percent). He also does a good job of reaching on outfield flies (.311, .278, .186 in 2007-09). When he does keep the ball in the infield, he’s decidedly above average at reaching first in this situation as well, doing so at 18-percent, 10-percent and 17-percent rates in recent years.
Young is simply a line-drive machine. He has not had fewer than 21.5 percent of his at-bats wind up as line drives in any of the last seven seasons, a shockingly good success rate at a statistic that has just a .37 correlation; he has had line-drive rates of 28 percent and 23 percent the previous two years. His strong swing also leads to very few pop-ups, doing so just 1.3 percent, 2.8 percent, and 2.9 percent of the time the last three years. He also is good at hitting hard ground balls, as his have reached the hole between 19-20 percent of the time the last four years in a row, above the league average of 17 percent.
Mauer is yet another player with downward plane to his swing, with ground-ball rates of 51 percent, 55 percent, and 51 percent in the last three years. He also popped up at an incredibly low rate of 1.9, 3.2, and 1.5 percent the last three years. His shockingly high .373 BABIP in 2009 was largely due to 26 percent of his ground balls reaching the outfield, but his recent years have been more modestly above average, ranging between 18-21 recent over the previous five seasons. Mauer is good at getting fly balls to fall in the outfield too, with outfield fly-ball BABIPs of .198, .220, and .196 the last three years, above the league average of .170. He also makes solid contact, missing with about 10 percent of his swings, which is about half as much as other hitters whiff. Overall, Mauer just hits, but you knew that.
Certainly not a regular superstar by any means, Lewis is at least a BABIP Superstar if he can actually hit the ball in play often enough. Unfortunately, Lewis has struck out in 24 percent and 25 percent of his PA the last two years, which is the reason (coupled with a home-run rate below 2 percent) that he likely will not start for the Giants this year. However, when Lewis does hit the ball, he hits a lot of ground balls (55 percent and 51 percent the last two years), few popups (2.6 percent and 4.3 percent), and reaches on his infield ground balls at a high rate too (14 percent and 15 percent).
Much of Choo’s .370 BABIP in 2009 was luck, just like anyone who has a .370 BABIP, but he still possesses a good amount of BABIP skill, as evidenced by his .367 BABIP in 2008. He avoids popups (5.3 percent and 3.4 percent the last two years), while getting hits to fall in the outfield at a good rate as well (27 percent and 24 percent vs. league average of 17 percent). He also hits his ground balls through the hole at a good rate too (26 percent and 21 percent vs. league average of 17 percent). Choo definitely has a swing that will drive the ball, but he still is unlikely to keep up his extremely high BABIP from last year.
David Wright’s power outage in 2009 was masked by his ridiculously high BABIP. Wright, like every other hitter in the league, is not good enough to reach on 39 percent of his balls in play every year, but he does have a solid skill at getting the hits to fall in. The main reason is his solid line-drive rate which has been 25 percent, 25 percent, and 26 percent the last three years. He also reaches on a decent number of his infield ground balls too, thanks to his 15-percent rate the last couple of years. He also has power historically, and that certainly proxies for being able to hit the ball hard.
Votto hits a lot of line drives (24 percent and 25 percent the last two years) and few popups (3.1 percent, 3.3 percent), which certainly explains most of his BABIP skill. His power (4.6 percent and 5.3 percent HR/AB in the last two years) also indicates he is hitting the ball very hard, as does his outfield fly-ball BABIP, which went from .196 in 2008 up to .281 in 2009.
BABIP Trouble in Cleats
Although it’s easier to detect the BABIP Superstars, because they generally tend to keep their jobs, there are some hitters who keep their jobs without getting many hits on balls in play. Since most plate appearances result in a ball in play, these are certainly not the worst people in the world at getting hits on BABIP, but just the worst among projected major-leaguers for next year. Starting from the bottom, here are the BABIP troublemakers.
The sister to the BABIP Superstars’ downward plane is the BABIP Troublemakers' upward plane. Encarnacion has generated ground-ball rates of just 38 percent, 34 percent, and 36 percent the previous three years, while generating pops on 15 percent, 20 percent, and 10 percent of balls in play. He reached on fewer infield ground balls this year (just 5 percent after 13 percent in 2007 and 15 percent in 2008), while also getting fewer of them to get to the outfield (trending from 23 percent in 2007, 16 percent in 2008, down to just 7 percent in 2009).
Barajas has the upward plane problem too, with just 33 percent, 37 percent, and 30 percent for his ground-ball rates the last three years, and high pop-up rates of 16 percent, 12 percent, and 15 percent to boot. Barajas also struggles to hit line drives, doing so just 13 percent, 16 percent, and 15 percent of the time the last three years. Barajas is also very slow, which makes it hard for him to beat out infield hits, though he was league average last season at reaching on infield ground balls (11 percent) after being around 7 percent the previous two years.
Blum is pretty much a guy with average home-run and strikeout rates, while also being someone who is pretty slow and has an upward plane to his swing. He also has had some trouble hitting line drives as well. His ground-ball rates have been 38 percent, 37 percent, and 37 percent the last three years, while his pop-up rates have been 10 percent, 13 percent, and 14 percent, and his line-drive rates have been 19 percent, 14 percent, and 18 percent.
PECOTA projects a rebound from Young in 2010 after struggling last year. However, his swing would certainly need to flatten back out for this to happen. His ground-ball rate fell from 38 percent in 2007 and 39 percent in 2008 down to 28 percent in 2009. His pop-up rate subsequently jumped from 12% in 2007 and 11% in 2008 up to a massively disappointing 22 percent in 2009. He does not make great contact, but is redeemed by his speed, as he has reached on 16 percent, 14 percent, and 16 percent of his infield ground balls.
Burrell has always had an uppercut swing, but has lost some of the power that kept his BABIP high in the process. His ground-ball rate has ranged from 31-34 percent the last few years, while his pop-up rate has gone from 12 percent in 2007 and 2008 to 9 percent in 2009. He is among the slowest players in baseball, so he won’t beat out many infield hits, and with his power falling, his outfield fly-ball BABIP has fallen too. Over the last six years, it has fallen gradually: .164, .181, .188, .124, .142, and then to .103 last year. Without a power resurgence, Burrell is going to have a lot of trouble, since his BABIP is low and his strikeout rate is pretty high. Much of his career value has come from home runs and walks, but with fewer home runs, pitchers won’t want to walk him either.
Looking through the BABIP Superstars and the BABIP Troublemakers, it’s pretty clear that the important factors in keeping up your BABIP are having a downward plane to your swing while still being able to square it up, and also some power and some speed. Part Three of this series will discuss the hitters on which PECOTA and E-BABIP differ the most.