Like many different nerds, I’ve devoted plenty of time to slicing and dicing Baseball Savant’s new bat monitoring knowledge over the previous couple of weeks. And like many different nerds, I’m not fully certain how we’ll find yourself utilizing this wealth of recent data. Extra time, extra knowledge, and extra mind energy is required to wring out no matter sweeping new truths it might maintain. I’m going to jot down about bat monitoring knowledge in a extra targeted manner subsequent week. There are a pair issues I feel are actually fascinating; not essentially new data, however ways in which bat monitoring knowledge may give us laborious numbers for issues that we’ve already realized. On this article, I’ll be a bit extra scattershot. I’d identical to to take you thru how I’ve processed all the knowledge that has come out over the previous couple of weeks.
First off, bat monitoring will give us new stats that stabilize extra rapidly than current ones, as that’s how granular metrics that separate underlying expertise from outcomes are likely to work. In smaller samples, exit velocity turned out to be a better predictor of total batting efficiency than wRC+ or wOBA. Now we now 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 in the course of the first week or fewer than 100 PA throughout all the 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 price higher than first-week hard-hit price (R = .66 for swing velocity, in comparison with R = .46 for hard-hit price). If, after the primary week, you need to know who’s going to hit the ball laborious for the remainder of the season, don’t have a look at exit velocity. Take a look at swing velocity:
That stated, I’m not constructive that this explicit manner of bat monitoring knowledge will assist anybody. We’re most likely breaking issues down too finely right here. In spite of everything, swing velocity doesn’t have that robust 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 price (R = .21 for each). It may well inform us sooner how laborious a participant is able to hitting the ball, but it surely’s not any faster at telling us how properly they’ll hit.
Second, I’ve heard good individuals say that this knowledge might forestall accidents. If fatigue, tightness, or tenderness is retaining you from swinging as laborious as you usually would, a watchful analyst might spot it within the numbers and prescribe relaxation earlier than you harm your self. Whereas this makes a certain quantity 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 price, 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 distinguished gamers with latest 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 truly swinging barely tougher in opposition to four-seamers within the week earlier than they acquired injured than they’d been earlier within the season.
To this point, my largest 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 when you’re making an attempt to study something, it is advisable choose your variables very, very fastidiously to ensure you’re evaluating apples to apples. If you wish to analyze swing velocity, it is advisable just be sure you’re accounting for pitch kind. As Ben Clemens has mentioned, faster 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. Because the candy spot of the bat usually begins out someplace above and behind the batter’s again shoulder, it has to journey a larger distance to succeed in a slider low and away than a fastball over the center. In case you’re swinging at an inside pitch, you’re extra prone to meet the ball out in entrance, which suggests a longer swing. So a participant who chases too many breaking balls is prone to get dinged for an extended swing, as is a right-handed Astro who makes a residing pulling balls into the Crawford Containers. A kind of is a nasty 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 wrestle to discover a consultant pattern. Whereas smarter individuals had been determining the issues I simply advised you, I used to be questioning concerning the energy of the connection between swing size and the peak of the batter. In spite of everything, there’s a purpose we anticipate larger gamers with longer levers to hit for extra energy. In case you look at Baseball Savant’s major bat monitoring leaderboard, you’ll see that Oneil Cruz has one of many longer swings within the recreation, which isn’t shocking since he’s one of many longer individuals within the recreation. Nevertheless, when you drill all the way 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 reduce our pattern manner 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 concentrate on these pitches, it seems that when he’s not flailing at breaking balls, Cruz has a surprisingly quick swing, under the massive league common on this explicit break up. Nevertheless, this will not be the suitable manner to take a look at issues. Possibly Cruz’s numbers look too rosy as soon as we’ve thrown out his many, many whiffs. Possibly we must always solely be whiffs. In spite of everything, 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 any contact. That’s an enormous variable eradicated. Once I seemed simply at whiffs on middle-middle fastballs, Cruz’s swing size was now not under 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 lots of my deep dives into bat monitoring knowledge, I’m not fully certain how you can make all the elements mix right into a cohesive complete. On this instance, it made plenty of sense to look solely at whiffs, however on the identical time, it appeared ludicrous to evaluate a participant’s swing velocity, which exhibits how a lot harm 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 manner in a short time. We’ve all learn articles about groups telling their pitchers to trust a certain pitch as a result of it’s nastier than they understand. 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 usually. He may be extra probably to purchase in when 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 understanding that batters can’t even get a very good swing off in opposition to a pitch may be simply as robust a motivator.
As I stated on the high, these are simply my first takeaways as I type by way of the information 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 preserve digging.
