Quantifying Hitter Plate Discipline with EAGLE: Part 2

Picture credit score: © Brad Mills-USA TODAY Sports activities

This idea was initially introduced at a SABR convention in March 2022 and has been tailored for publication at Baseball Prospectus.

In our previous article, we mentioned the event of the EAGLE metric by means of an strategy quantifying the anticipated change in run expectancy for every swing/take choice. On this article, we describe its efficiency at predicting efficiency and consider hitters with it. First, we will see that EAGLE correlates nicely with widespread plate self-discipline metrics like O% and BB% within the graphs beneath.

These relationships are a superb signal as a result of they inform us that EAGLE actually measures one thing, that we have now created a metric that measures a participant’s capability to make choices on the plate. One other characteristic of a nicely performing metric is stability from yr to yr, indicating it measures a real participant attribute quite than merely reflecting noise. That is particularly vital for a plate self-discipline metric as a result of we’d count on a participant’s choice making capability to be comparatively fixed all through from yr to yr. Until a participant makes a big change to their strategy on the plate, EAGLE ought to keep comparatively secure over time. We present right here that EAGLE is secure with a correlation of .452 from yr to yr.

Whereas EAGLE captures conventional plate self-discipline ideas, its true power is the way it measures the complete vary of outcomes from every choice to swing or to not swing. In doing this, EAGLE takes into consideration the slugging facet of baseball as nicely, by predicting what pitches are more likely to be hit for further bases. As proven beneath, EAGLE has a robust relationship with On-base Plus Slugging (OPS) with a correlation of .508. No different plate self-discipline statistics take this facet of baseball into consideration. Chase fee solely has a correlation with OPS of -.104.

EAGLE also can not solely be used to clarify the present season’s OPS, however to foretell subsequent yr’s OPS as nicely, displaying the predictive energy that this metric has. Under is a desk of percentiles and their EAGLE in addition to their corresponding OPS predictions. There’s a important distinction between the upper and decrease percentiles in predicted OPS and reveals that EAGLE can discriminate between good and dangerous hitters each now and sooner or later. Moreover beneath reveals a desk cut up up by sections of 20% of hitters in EAGLE and their common predicted OPS for this yr and for subsequent yr to indicate that these predictions work when utilized to hitters. Bucket 1 is the underside 20% of hitters in EAGLE and bucket 5 is the highest 20% of hitters in EAGLE.

Now after proving EAGLE is a brand new and progressive metric, we will now use it to see which hitters are literally the perfect at making choices on the plate. Under is a desk of the perfect and worst hitting seasons when it comes to EAGLE over the previous 5 years. To be extra clear, these are the runs generated per pitch by the hitter’s choices.

Among the gamers generally perceived as plate self-discipline greats are on the high right here like Joey Votto and Juan Soto and among the extra free swingers and aggressive hitters are in direction of the underside like Jose Iglesias and Dee Unusual-Gordon. Now we’ve seen how EAGLE could be aggregated, however what’s additionally helpful about EAGLE is that it may be utilized on a pitch by pitch degree, so let’s check out just a few situations right here.

Here’s a swing that many baseball followers have in all probability seen cross their social media feeds. That is Anthony Santander swinging at a Charlie Morton curveball that manages to undergo his legs. Clearly a foul choice, and EAGLE will let you know that this swing was value -.098 runs as a result of likelihood of a swing and miss on this pitch being .803. The desk beneath breaks down the EAGLE estimate for this pitch. The anticipated possibilities in addition to the run expectations pre-pitch are given, every part wanted to calculate EAGLE apart from the run expectations of every consequence.

And as you may inform, nothing good was going to occur on this pitch, an clearly dangerous choice to swing. Let’s check out a extra excessive stakes state of affairs. This choice to swing by Byron Buxton with the bases loaded value the Twins -.910 runs, a way more pricey choice due to the state of affairs. That is clearly a foul pitch outdoors of the strike zone and ends in a swing and miss likelihood of .857.

These subsequent two examples usually are not swings and misses. Though this subsequent pitch is the costliest of all three we’ve seen up to now. Austin Hedges decides to take strike three proper down the center of the plate in a bases loaded state of affairs for the third out of the inning. Clearly a horrible choice and it prices his staff about -1.659 runs. If he had swung, we estimate a ten.1% probability of a house run.

This closing instance is Seattle catcher Tom Murphy. He swings at a pitch proper down the center and cranks it down the left area line simply barely to the left of the foul pole. As a fan, you’re upset that it’s only a foul ball, however Murphy needs to be rewarded for his choice to swing right here. With a .453 likelihood of a homerun on this pitch his choice to swing added a predicted .953 runs.

This ends the EAGLE saga and you may take a look at the EAGLE app here which incorporates 2019 EAGLE information. The following factor we’ve achieved with EAGLE is examine its use for pitchers. This tells how good pitchers are at being misleading, or inflicting hitters to make the mistaken choice. We’ve damaged down pitching efficiency into stuff, management, and EAGLE to foretell and clarify total pitching efficiency and we’ve encapsulated that into this brand new app which features a 2022 characteristic web page that’s up to date on a regular basis and contains operating hitter EAGLEs for 2022 as nicely. There’s loads extra investigating to do into the makes use of of EAGLE so keep tuned for extra updates.

Joshua Mould is a Junior at Villanova College finding out Laptop Science and Statistics and might be an Affiliate Quantitative Analyst this summer season with the Philadelphia Phillies
David Anderson is the Michele and Christopher Iannaccone ‘91 Assistant Professor of Analytics on the Villanova College of Enterprise