Like many different nerds, I’ve devoted a number 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 solely 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 put in writing about bat monitoring knowledge in a extra centered 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 arduous numbers for issues that we’ve already realized. On this article, I’ll be a bit extra scattershot. I’d similar 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 shortly than present ones, as that’s how granular metrics that separate underlying abilities from outcomes are inclined to work. In smaller samples, exit velocity turned out to be a higher predictor of total batting efficiency than wRC+ or wOBA. Now we now 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 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 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 wish to know who’s going to hit the ball arduous for the remainder of the season, don’t take a look at exit velocity. Have a look at swing pace:
That stated, I’m not optimistic that this explicit 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 spite of everything, swing pace 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 pace has a barely decrease correlation (R = .19) to full-season wOBA than exit velocity or hard-hit price (R = .21 for each). It could inform us sooner how arduous a participant is able to hitting the ball, nevertheless it’s not any faster at telling us how nicely they will hit.
Second, I’ve heard good folks say that this knowledge may stop accidents. If fatigue, tightness, or tenderness is preserving you from swinging as arduous 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 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 outstanding 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 have been truly swinging barely tougher in opposition to four-seamers within the week earlier than they received injured than that they had been earlier within the season.
Thus far, my largest takeaway is an apparent one: Bat monitoring could be very sophisticated. There are such a lot of components that have an effect on swing pace and size, and for those who’re attempting to be taught something, you want to choose your variables very, very rigorously to be sure to’re evaluating apples to apples. If you wish to analyze swing pace, you want to just remember to’re accounting for pitch sort. As Ben Clemens has mentioned, sooner pitches elicit slower swings. After all, swing pace can be correlated with swing size, and swing size is correlated with location, and site is correlated with pitch sort, and now we’re again the place we began. Because the candy spot of the bat typically begins out someplace above and behind the batter’s again shoulder, it has to journey a larger 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 a longer swing. So a participant who chases too many breaking balls is more likely to get dinged for an extended swing, as is a right-handed Astro who makes a dwelling pulling balls into the Crawford Containers. A type of is a nasty factor, and a type 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 in regards to the energy of the connection between swing size and the peak of the batter. In spite of everything, there’s a cause we anticipate greater gamers with longer levers to hit for extra energy. For those who look at Baseball Savant’s primary bat monitoring leaderboard, you’ll see that Oneil Cruz has one of many longer swings within the sport, which isn’t shocking since he’s one of many longer folks within the sport. Nevertheless, for those who 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 minimize our pattern means down, however we’re doing our greatest to manage for the sort, pace, and site 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 brief swing, beneath the large league common on this explicit break up. Nevertheless, this will not be the fitting means to have a look at issues. Possibly Cruz’s numbers look too rosy as soon as we’ve thrown out his many, many whiffs. Possibly we should always solely be taking a look at whiffs. In spite of everything, 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 a contact. That’s an enormous variable eradicated. Once 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.
Irrespective 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 fully certain the right way to make all the elements mix right into a cohesive complete. On this instance, it made a number 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 can 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 understand. They’ll now be capable of level to a particular 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 a very good 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 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 maintain digging.
