Category: Asides

A Note on Statcast Data

We are now in the fifth year of the so-called “Statcast Era” (which is still the most misleading way to say “since 2015” in professional sports), and the use of the new data is becoming ubiquitous. We use it often here at Views, citing now-familiar metrics like exit velocity, spin rate, barrels to help paint a complete picture of a player’s profile. Despite being mocked fairly regularly, much of the Statcast data is useful for analysis. It really is.

However, it’s important to not get complacent in our use of data–and Jonathan Judge of Baseball Prospectus ably reminded everyone last week of Statcast’s limitations. The study is free to read even if you don’t have a Prospectus subscription (you should, they’re excellent), and I recommend you check it out for yourself. I did want to pull out a few top-level highlights, though, because I think it’s an important reminder that even the most neutral sounding data points are often biased in hidden ways.

  • Park factors matter for exit velocity, too: This might seem counterintuitive (a ball is hit hard or it isn’t, right?), but the overall point of this study, and its accompanying series, is to determine the ways in which different stadiums change exit velocity/launch angle data. Elevation and other externalities (such as whether a stadium houses their baseballs in a humidor) may change the way balls are hit, and the reality is that, as Judge puts it, “different stadiums may have different Statcast installations in different orientations in varying states of operation.” It’s a significant challenge, and while the league has made improvements in this regard, it’s an important factor to keep in the back of your mind as you digest the slew of Statcast data thrown at you each day in broadcasts and online.
  • Even seemingly-small park factors make a big difference: The study found variance of 0.5 mph in either direction per park to be common, and even found that, for individual players, the variance can be as high as 2 mph. That can equal 10 extra feet of distance. There is a lot of noise over the course of a full MLB season–players don’t play in just one stadium, of course–but this is worth keeping in mind.
  • Not all batted balls are created equally: This is, I think, the most important reminder from the study. Given the amount of batted ball events that occur each season, it’s inevitable that some will not be properly recorded for one reason or another. When insufficient data is recorded, MLB’s “no nulls” policy means that an MLB statistician estimates the exit velocity/launch angle based on similar plays. It does not, however, denote which plays are manually-inputed and which are recorded. As you can imagine, that is a problem–with no way to tell what is real and what is not, it creates a real analytical problem for the public.

Check out the full study for a more in-depth (and, to my delight, significantly wonkier) explanation of the finding, and stay tuned for updates in the series. It’s worth reading yourself. Also, as a brief aside, the introduction of new park elements to Statcast is yet another way to peel back an additional layer of analysis to describe what we see on the field. Exciting!

I quite like the Statcast revolution, and I find the data to be useful from an analytical perspective. As a Yankee fan, you should too–good batted ball profiles are how they found Luke Voit and DJ LeMahieu, after all. But it’s important to always recognize the limitations of the data we use here at 314ft.

This new series at Baseball Prospectus is a good reminder that even though Statcast data is useful and informative, it does not tell us everything.

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An Appreciation for the Hospital Yankees

This is a stupid way to start my first post on a Yankees blog, but I have to confess something: I’m a Boston Celtics fan. I know, I know, I’m sorry, but I swear this relates to the Yankees.

The Celtics have put their fans through a rollercoaster for the last three years as they tried (and seemingly failed) to become an NBA juggernaut. They traded the fan base’s favorite player, the 5-foot-9 Isaiah Thomas, just after he led them to the conference finals in an emotional flourish.

For Thomas, they acquired “basketball genius” Kyrie Irving, who needed knee surgery before season’s end. They also signed Gordon Hayward to a max contract just for him to severely injure his ankle five minutes into his first game. The Celtics limped into the 2018 postseason to the point where teams competed to face them instead of others, seeing them as an easy out.

Instead, Boston made another run to the conference finals with what was described by the denizens of the internet as the “Hospital Celtics”. Missing a few of their best players, they relied on a young and unproven core to beat future MVP Giannis Antetokounmpo and then the rival Sixers, only to be felled by LeBron James.

The next season, with everyone healthy, the team was an unmitigated disaster, leading to a second-round exit and plenty of finger pointing. The 2018-19 Celtics were such an insufferable bunch that the season’s end was a welcome relief. They had me pining for the previous year’s team, the one no one expected would emerge yet found ways to win shorthanded, one that made mincemeat of 20-point deficits.

So when the Celtics fell out of the 2019 playoffs, I quickly turned to the Yankees and saw something familiar, the Hospital Yankees. The Yankees won’t stay the Hospital Yankees forever, but it’s imperative to enjoy them while they keep defying expectations. Heck, at this point, we expect the Down-14-players Yankees to win games, which says something else entirely. It hasn’t been just one pitcher getting a rest or a couple hitters hitting the IL; It’s everyone who’s anyone finding time to sit in an MRI tube.

For all intents and purposes, these Yankees should be .500 at best, right? They’re missing their No. 1, No. 2, No. 4 and No. 7 starters, their best reliever, arguably their two best hitters as well as Didi Gregorius, Miguel Andujar and more. There would have been plenty of disappointment but no shame in this team taking a year off from the postseason, unable to keep it together while hoping to get healthy the next year. The 2014 Rangers, a parallel from the past, did so before winning the division the next two seasons.

After all, the 2019 Yankees have had 100 combined starts from Mike Tauchman, Gio Urshela, Mike Ford, Kendrys Morales and Cameron Maybin, none of whom were on the 40-man roster before March 20th. Domingo German has gone from questionable depth starter to the American League leader in wins. Wins don’t carry the same weight they used to, but the numbers display German’s progress.

Just as the 2017-18 Celtics, the Hospital Yankees’ success has been buoyed by a few expected sources holding things together as a strong adhesive. New York has leaned hard upon Gary Sanchez, Gleyber Torres, Masahiro Tanaka and the bullpen and each has answered the call. You can’t win just from players coming out of nowhere: They even need some help.

Still, how can you not enjoy what the Tauchmans and Urshelas have done? We’ve gone from pain seeing their names in the lineup to a grudging respect to genuinely excited for their at-bats.

After seeing the Celtics come apart at the seams this year, it’s increased my appreciated for what Jayson Tatum, Marcus Smart and the Hospital Celtics achieved last season. I wish I had done so at the time and I won’t make the same mistake with this year’s Yankees. I’m obviously waiting impatiently for each injured contributor’s return, but I’m going to enjoy every second of this improbable, un-Yankee-like run. There won’t be anything like this stretch for a while.

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