Like many different nerds, I’ve devoted a whole lot 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 completely certain 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 jot down about bat monitoring knowledge in a extra targeted means subsequent week. There are a pair issues I feel are actually fascinating; not essentially new info, however ways in which bat monitoring knowledge can provide us laborious numbers for issues that we’ve already discovered. On this article, I’ll be a bit extra scattershot. I’d similar to to take you thru how I’ve processed all the data that has come out over the previous couple of weeks.
First off, bat monitoring will give us new stats that stabilize extra shortly than present 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 higher predictor of general batting efficiency than wRC+ or wOBA. Now now we have swing pace, 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 general numbers this season. I eradicated any participant with fewer than 5 plate appearances through 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 pace (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 pace, 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 take a look at exit velocity. Take a look at swing pace:
That stated, I’m not optimistic that this specific means of taking a look at bat monitoring knowledge will assist anybody. We’re in all probability breaking issues down too finely right here. In any case, swing pace doesn’t have that sturdy a correlation to general success on the plate, a lot decrease than exit velocity. If we return to our first-week stats, swing pace has a barely decrease correlation (R = .19) to full-season wOBA than exit velocity or hard-hit price (R = .21 for each). It will possibly inform us sooner how laborious a participant is able to hitting the ball, however it’s not any faster at telling us how effectively they will hit.
Second, I’ve heard sensible folks say that this knowledge may forestall accidents. If fatigue, tightness, or tenderness is holding you from swinging as laborious as you usually would, a watchful analyst may 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. Folks have been attempting 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 current accidents: Ronald Acuña Jr. and Steven Kwan. Not that this implies something, particularly with two decrease physique accidents, however each Acuña and Kwan have been truly swinging barely more durable in opposition to four-seamers within the week earlier than they bought injured than they’d been earlier within the season.
To this point, my greatest takeaway is an apparent one: Bat monitoring may be very difficult. There are such a lot of elements that have an effect on swing pace and size, and for those who’re attempting to be taught something, you could choose your variables very, very rigorously to ensure you’re evaluating apples to apples. If you wish to analyze swing pace, you could just be sure you’re accounting for pitch kind. As Ben Clemens has mentioned, sooner pitches elicit slower swings. In fact, swing pace can also be correlated with swing size, and swing size is correlated with location, and site is correlated with pitch kind, and now we’re again the place we began. For the reason that candy spot of the bat usually 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. In the event you’re swinging at an inside pitch, you’re extra prone to meet the ball out in entrance, which implies a longer swing. So a participant who chases too many breaking balls is prone to get dinged for a protracted swing, as is a right-handed Astro who makes a residing pulling balls into the Crawford Containers. A type 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 folks have been determining the issues I simply advised you, I used to be questioning concerning the power of the connection between swing size and the peak of the batter. In any case, there’s a motive we anticipate larger gamers with longer levers to hit for extra energy. In the event you look at Baseball Savant’s principal 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 folks within the sport. Nevertheless, for those who 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 lower our pattern means down, however we’re doing our greatest to manage for the kind, pace, and site 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 brief swing, beneath the massive league common on this specific cut up. Nevertheless, this is probably not the best means to have 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 taking a look at whiffs. In any case, if we simply take 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. After I appeared simply at whiffs on middle-middle fastballs, Cruz’s swing size was not beneath common, though it was nonetheless comparatively brief 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 certain methods to make all the components mix right into a cohesive complete. On this instance, it made a whole lot of sense to look solely at whiffs, however on the identical time, it appeared ludicrous to evaluate a participant’s swing pace, which reveals how a lot injury they will do on contact, by throwing out all of the swings the place they really made contact!
I think that bat monitoring shall be utilized in one specific 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 understand. They’ll now be capable 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 for those who 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 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 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.