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Exit velocity (EV) is one of the most often talked about Statcast metrics. It’s one of the most simple to understand, since it is merely an average of how hard a hitter hits the ball. However, it’s also flawed to an extent, especially in smaller sample sizes.
While the stabilization point of exit velocity for a hitter is relatively early at just 16 games played, it can still be easily skewed by a few particularly hard hit batted balls, or conversely, particularly softly hit ones. This is why we often pivot to hard hit rate, since it measures the frequency of which a hitter is making hard contact. However, hard hit rate takes nearly twice as long to stabilize, taking approximately 29 games.
Statcast has a newer metric called EV50 that may help to further evaluate hitters. For hitters, EV50 is simply the average of the hardest 50% of batted balls. For pitchers, it’s an average of the softest 50% of batted balls. Before we dive into the differences between EV and EV50, let’s first take a look at how Reds hitters stack up in each this year. We will only include hitters with at least 50 batted balls this season. All stats are through Monday’s game.
The first thought might be that players with a higher hard hit rate might also have a higher EV50. This seems to be partially true, as we can see to an extent between Stuart Fairchild, Nick Martini, and Jonathan India. While each have identical average EVs, Fairchild has the highest hard hit rate and also the highest EV50.
However, this isn’t necessarily true for all hitters. While Tyler Stephenson has a higher hard hit rate than Elly De La Cruz, Stephenson has a lower EV50. Interestingly, Stephenson and De La Cruz each have hard hit rates over 50%, meaning that their EV50 value contains an average of only hard hit balls. Will Benson’s EV50 contains just one batted ball that would not be considered hard hit.
One advantage EV50 may have is that since it excludes the hitter’s softest batted balls, it may be a better measure of a hitter’s pure power. Those with higher EV50 values could generally be assumed to be hitters with more raw power, something that seems to hold water given that De La Cruz leads the team, and also ranks 15th in all of baseball, in EV50. However, he also leads the team and ranks 15th in the league in EV.
Christian Encarnacion-Strand is one standout in EV50. While he ranks sixth on the team in EV, he ranks fourth in EV50. This could be due to a few different factors. His hard hit batted balls could be harder hit than others, his softest hit batted balls could be softer than others, his hard hit rate could be higher, or a combination of the three.
One other Red worth mentioning is Jake Fraley. Though he currently sits with a .305 average and 117 wRC+, he hasn’t been hitting the ball hard this season by any of the three metrics. It’s a massive dropoff in power this season for someone who already ranked near the bottom of the league in hard hit rate and exit velocity last season. It will be worth monitoring to see if Fraley is able to have continued success despite hitting the ball with less authority.
Ultimately the key question in the EV50 discussion is whether EV50 provides anything more useful than what we can already get from other metrics. According to Tom Tango, as noted on the Baseball Savant website, EV50 provides a significantly higher correlation with a hitter’s next season wOBAcon, a key measure of a hitter’s quality of contact. This means identifying hitters with higher EV50 values could help better predict future success for that hitter. From that perspective, EV50 outperforms EV, much like advanced pitching metrics like FIP, xFIP, and SIERA are all better at predicting a pitcher’s future performance than ERA.
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