Like many different nerds, I’ve devoted quite a lot of time to slicing and dicing Baseball Savant’s new bat monitoring knowledge over the previous few weeks. And like many different nerds, I’m not solely positive how we’ll find yourself utilizing this wealth of recent info. Extra time, extra knowledge, and extra mind energy is required to wring out no matter sweeping new truths it could maintain. I’m going to write down about bat monitoring knowledge in a extra centered means subsequent week. There are a pair issues I believe are actually attention-grabbing; not essentially new info, however ways in which bat monitoring knowledge can provide us exhausting numbers for issues that we’ve already discovered. On this article, I’ll be a bit extra scattershot. I’d identical to to take you thru how I’ve processed all the data that has come out over the previous few weeks.
First off, bat monitoring will give us new stats that stabilize extra shortly than current ones, as that’s how granular metrics that separate underlying abilities from outcomes are likely to work. In smaller samples, exit velocity turned out to be a greater predictor of total batting efficiency than wRC+ or wOBA. Now now we have swing velocity, which in smaller samples seems to be a greater predictor of exit velocity. To wit, I pulled knowledge from the primary week of bat monitoring, April 3 to April 9, and in contrast it to every participant’s total numbers this season. I eradicated any participant with fewer than 5 plate appearances throughout the first week or fewer than 100 PA throughout your entire season, which left me with a pattern of 295 gamers. It was no contest. Full-season exit velocity had a a lot stronger correlation to first-week swing velocity (R = .60) than it did to first-week exit velocity (R = .40). It additionally predicted full-season hard-hit fee higher than first-week hard-hit fee (R = .66 for swing velocity, in comparison with R = .46 for hard-hit fee). If, after the primary week, you need to know who’s going to hit the ball exhausting for the remainder of the season, don’t have a look at exit velocity. Have a look at swing velocity:
That stated, I’m not optimistic that this explicit means of bat monitoring knowledge will assist anybody. We’re in all probability breaking issues down too finely right here. In any case, swing velocity doesn’t have that sturdy a correlation to total success on the plate, a lot decrease than exit velocity. If we return to our first-week stats, swing velocity has a barely decrease correlation (R = .19) to full-season wOBA than exit velocity or hard-hit fee (R = .21 for each). It may well inform us sooner how exhausting a participant is able to hitting the ball, however it’s not any faster at telling us how effectively they’ll hit.
Second, I’ve heard good individuals say that this knowledge may stop accidents. If fatigue, tightness, or tenderness is preserving you from swinging as exhausting as you usually would, a watchful analyst may spot it within the numbers and prescribe relaxation earlier than you damage your self. Whereas this makes a specific amount of sense, I’m skeptical for now. Individuals have been making an attempt to do the identical factor with pitchers for years, monitoring stride size, extension, launch level, velocity, spin fee, and break for indications of fatigue or compensation. To my data, nobody has cracked that code but. For some fast anecdotal analysis, I checked two outstanding gamers with current accidents: Ronald Acuña Jr. and Steven Kwan. Not that this implies something, particularly with two decrease physique accidents, however each Acuña and Kwan had been really swinging barely more durable in opposition to four-seamers within the week earlier than they bought injured than that they had been earlier within the season.
Thus far, my greatest takeaway is an apparent one: Bat monitoring may be very difficult. There are such a lot of components that have an effect on swing velocity and size, and in case you’re making an attempt to be taught something, it’s essential to choose your variables very, very rigorously to be sure to’re evaluating apples to apples. If you wish to analyze swing velocity, it’s essential to just remember to’re accounting for pitch kind. As Ben Clemens has mentioned, quicker pitches elicit slower swings. After all, swing velocity can also be correlated with swing size, and swing size is correlated with location, and placement is correlated with pitch kind, and now we’re again the place we began. For the reason that candy spot of the bat typically begins out someplace above and behind the batter’s again shoulder, it has to journey a higher distance to achieve a slider low and away than a fastball over the center. For those who’re swinging at an inside pitch, you’re extra more likely to meet the ball out in entrance, which implies an extended swing. So a participant who chases too many breaking balls is more likely to get dinged for a protracted swing, as is a right-handed Astro who makes a residing pulling balls into the Crawford Bins. A kind of is a foul factor, and a kind of is a part of the explanation that Jose Altuve and Alex Bregman are perennial All-Stars.
Right here’s an instance of the battle to discover a consultant pattern. Whereas smarter individuals had been determining the issues I simply informed you, I used to be questioning in regards to the energy of the connection between swing size and the peak of the batter. In any case, there’s a cause we count on larger gamers with longer levers to hit for extra energy. For those who look at Baseball Savant’s major bat monitoring leaderboard, you’ll see that Oneil Cruz has one of many longer swings within the sport, which isn’t stunning since he’s one of many longer individuals within the sport. Nonetheless, in case you drill right down to get a extra consultant pattern, issues change.
Let’s say you look solely at aggressive swings on middle-middle fastballs that resulted in balls hit straightaway. We’ve lower our pattern means down, however we’re doing our greatest to manage for the kind, velocity, and placement of the pitch, in addition to the depth of contact. If we give attention to these pitches, it seems that when he’s not flailing at breaking balls, Cruz has a surprisingly quick swing, beneath the massive league common on this explicit break up. Nonetheless, this is probably not the correct means to take a look at issues. Perhaps Cruz’s numbers look too rosy as soon as we’ve thrown out his many, many whiffs. Perhaps we should always solely be whiffs. In any case, if we simply have a look at whiffs, we don’t have to fret about accounting for depth of contact, as a result of there isn’t a contact. That’s an enormous variable eradicated. After I regarded simply at whiffs on middle-middle fastballs, Cruz’s swing size was not beneath common, though it was nonetheless comparatively quick for such a tall participant.
Regardless of how I sliced it, I tended to seek out that peak and swing size had a correlation coefficient between .24 and .35. Nonetheless, as with so a lot of my deep dives into bat monitoring knowledge, I’m not utterly positive the way to make all the components mix right into a cohesive entire. On this instance, it made quite a lot of sense to look solely at whiffs, however on the identical time, it appeared ludicrous to guage a participant’s swing velocity, which reveals how a lot injury they’ll do on contact, by throwing out all of the swings the place they really made contact!
I believe that bat monitoring will likely be utilized in one explicit means in a short time. We’ve all learn articles about groups telling their pitchers to belief a sure pitch as a result of it’s nastier than they notice. They’ll now have the ability to level to a selected quantity. Let’s say you’re the Rays and also you need Garrett Cleavinger to throw his four-seamer extra typically. He is perhaps extra probably to purchase in in case you inform him that batters are swinging three ticks softer in opposition to it than they’re in opposition to his cutter and his sinker. Whiffs are nice, however figuring out that batters can’t even get a great swing off in opposition to a pitch is perhaps simply as sturdy a motivator.
As I stated on the high, these are simply my first takeaways as I kind by the info and course of what smarter baseball analysts have written on the subject. I’ll be again with extra subsequent week, and within the meantime, I’ll hold digging.
