QOP / QOPA

Quality of Pitch = QOP

Quality of Pitch Average = QOPA

Quality of Pitch is a relatively new metric that was introduced at the 2015 SABR conference and shows great promise. It is the first widely regarded metric that designates a ‘pitch value’ for every ball hurled at a catcher. While most existing pitching metrics focus on the outcome of the pitch, QOP focuses exclusively on the pitch itself.

It tracks & assigns values to these components of a pitch:

  1. Velocity
  2. Location (Proximity to Strike Zone Corners)
  3. Rise
  4. Break, Vertical
  5. Break, Horizontal
  6. Break, Late

The Calculation:

QOP = Velocity + Greiner Index (GI)

GI = -2.51 (RISE) + 1.88 (BREAK POINT) – 0.47 (LOCATION CHANGE) + 0.51 (TOT BREAK)

The Score:

Almost every pitch recorded since 2008 falls in the range of 0 – 10 (The MLB average is ~4.5 with a median of 5). That said, really good (or truly bad) pitches can fall outside of that range. Here is the scale the creators recommend as a reference:

Application

Let’s consider three different pitches from the 2014 season (all slides from QOPBaseball):

  1. Kershaw: Fastball – Good Velocity / Poor Location / No Break = 2.96 qop
  2. Ryu: Curveball – Decent break / Very Late Break / Very Good Location = 8.09 qop
  3. Beckett: Change Up – Poor Velocity / Very Poor Location / = -2.49 qop

Context

Top 10 Brewers Currently on the Roster (01/09/2019):

screen shot 2019-01-09 at 4.34.51 am

  • We see that Stearns’ newest left-handed addition tops the list! Good news for the greatest bullpen in baseball 🙂
    • The three guys on the bottom of the list find themselves at a crossroads in their career. Their ability to execute a higher rate of ‘quality pitches’ in 2019 will determine their baseball fates.
  • It is reassuring to see Burnes and Woody, the ‘arms of the future,’ ranking high on this list.
    • Their almost identical scores fall in between ‘MLB average’ and ‘good quality’ on the QOP scale (above). Not bad for budding prospects…

Corbin Burnes Entire 2019 QOP/QOPA Chart:

screen shot 2019-01-09 at 5.17.43 am

  • NOTE: This data is also broken into pitch-type (as seen here with Burnes)

The Top 10 Pitchers – QOPA, 2018:

  • Yes, 1-4 Tim Hill with the 4.53 ERA tops the list… confusing until you realize that he had a xFIP of 3.31, a GB% of 61.8%, and a SIERA of 3.18… numbers that approach elite levels.
    • Tim Hill’s talent is not reflected in his more superficial stats.
      • Once the more modern metrics are applied, including the QOP data, a more complete picture surfaces. One can see how ERA, the old stand-by stat, does not tell the whole story and can be misleading on its own.
        • Keep in mind… the classic pitching metrics are influenced by things a pitcher cannot control. QOP emphasizes what he can.

Team Pitching – QOPA, 2018:

screen shot 2019-01-09 at 4.10.57 am

  • MILWAUKEE: In 2018, Milwaukee was tied for 26th in the league for team qop (tied with MIN)
    • Only TOR, SEA, BAL and CLE were worse

The team data is also stratified by pitch-type:

Screen Shot 2019-01-09 at 4.14.31 AM.png

If you would like to expand your pursuits of QOP/QOPA, start with the qopbaseball site. Jason Wilson and Wayne Greiner, the creators of the QOP metric, have made their entire database available. Even if you are not a stat nerd, it is fun to use and easy to manipulate. There is both player and team data going back to 2008. We hope this summary helps you hit the ground running!

In the end, QOP/QOPA is still evolving and being studied in its different applications. The founders are making new data available all the time. As the topic grows, BREW MATHs will update this page…