Adjusting Old Scores to Match New Sheets

June 27, 2020
drum-corona-international

In my first post about Drum Corona International, I wrote about how I could refactor my DCI forecast model to simulate the 2020 season, and I’ve since hosted a vote to determine which shows will compete. Voting is open for one more day, but there’s one thing regarding scores I conveniently left out from my original post: how will I compare scores from different eras?

If you’re a younger DCI fan, it may not be an intuitive question - hasn’t DCI scoring always been the same? In current DCI scoring, there are three captions: General Effect, Music, and Visual. GE is worth 40 points and Music and Visual are worth 30 each. This seems like such an obvious format it’s easy to think it’s been around forever.

This 40-30-30 format was introduced in 2000. The 20 years since have been a pretty prolonged period of scoring stability compared to the rest of DCI (and drum corps) history, but there’s been many changes to the judging sheets themselves 1. For better or worse, my DCI model doesn’t care about these smaller changes 2, but the 40-30-30 format is a bedrock assumption to the model. It simply can’t handle scores that aren’t in that format intelligently.

Before 2000, the DCI sheets weren’t as stable. GE has been worth 40 points for some time, but the relative balance between Music and Visual was much more fluid, as were the subcaptions within them. In cases where the balance isn’t 30 points each, we need to adjust the old scores to match the 2020 format that the model expects.

We do this by approximating, as best we can, what a corps would have scored in the new sheets based on their subcaption scores. Any brass or percussion scores (outside of GE) are collected into the Music caption of our adjusted scores, while guard and other visual scores (like Field Visual) find a home in the Visual caption.

For example, here’s the recap from DCI FInals in 1993:

Brass
Percussion
Visual
Corps GE Field Ensemble Total Field Ensemble Total Field Ensemble Total Total
The Cadets 39.3 9.6 9.7 19.3 9.5 9.7 19.2 9.7 9.9 19.6 97.4
Star of Indiana 39.1 9.7 9.9 19.6 9.6 9.8 19.4 9.4 9.8 19.2 97.3
Phantom Regiment 38.9 9.6 9.6 19.2 9.2 9.6 18.8 9.8 9.5 19.3 96.2
Blue Devils 38.3 9.8 9.8 19.6 9.1 9.2 18.3 9.3 9.6 18.9 95.1
Cavaliers 38.0 9.4 9.2 18.6 9.3 9.5 18.8 9.5 9.1 18.6 94.0
Madison Scouts 37.0 9.4 9.4 18.8 8.7 9.2 17.9 9.0 9.2 18.2 91.9
Santa Clara Vanguard 36.5 9.3 8.7 18.0 9.4 9.1 18.5 8.6 8.8 17.4 90.4
Crossmen 36.7 8.7 8.9 17.6 8.9 8.6 17.5 8.8 9.0 17.8 89.6
Bluecoats 35.5 9.0 9.0 18.0 8.4 8.8 17.2 8.2 8.3 16.5 87.2
Blue Knights 33.8 8.8 8.6 17.4 8.6 8.7 17.3 8.3 8.2 16.5 85.0
Glassmen 33.6 8.3 8.3 16.6 7.9 8.3 16.2 8.0 8.4 16.4 82.8
Colts 33.6 8.0 8.4 16.4 7.7 8.4 16.1 7.8 7.7 15.5 81.6

In this recap, Brass and Percussion were treated as separate top-level captions, but we need to combine them into the Music Caption. The visual caption can remain unchanged 3. However, doing this would distribute the 100 possible points as 40 GE, 40 Music, and 20 Visual - the model can’t handle this. In order to get everything to the modern 40-30-30 format, we have to multiply the Visual score by 1.5 and multiply the Music score by 0.75.

Music
Visual
Total
Corps GE Brass Percussion Adjusted Visual Adjusted Old Adjusted
The Cadets 39.3 19.3 19.2 28.875 19.6 29.40 97.4 97.575
Star of Indiana 39.1 19.6 19.4 29.250 19.2 28.80 97.3 97.150
Phantom Regiment 38.9 19.2 18.8 28.500 19.3 28.95 96.2 96.350
Blue Devils 38.3 19.6 18.3 28.425 18.9 28.35 95.1 95.075
Cavaliers 38.0 18.6 18.8 28.050 18.6 27.90 94.0 93.950
Madison Scouts 37.0 18.8 17.9 27.525 18.2 27.30 91.9 91.825
Santa Clara Vanguard 36.5 18.0 18.5 27.375 17.4 26.10 90.4 89.975
Crossmen 36.7 17.6 17.5 26.325 17.8 26.70 89.6 89.725
Bluecoats 35.5 18.0 17.2 26.400 16.5 24.75 87.2 86.650
Blue Knights 33.8 17.4 17.3 26.025 16.5 24.75 85.0 84.575
Glassmen 33.6 16.6 16.2 24.600 16.4 24.60 82.8 82.800
Colts 33.6 16.4 16.1 24.375 15.5 23.25 81.6 81.225

Overall the effect is marginal but noticeable. The Cadets excelled visually on Finals night, so they got a bit more of a boost than in the original sheets because visual is worth more now. The order of placement wasn’t affected, and scores generally move less than a half point. I looked at several recaps that needed this adjustment, and this one is pretty representative.

Every recap from 1993 through 1999 was adjusted in this way for Drum Corona International. This doesn’t necessarily preserve the total score relative to the real world, which means the scores used to feed Drum Corona International won’t match the exact scores from the past. This can work both for and against corps with adjusted scores, depending on which captions they were strong in. If they were strong in a caption that was worth less than it is now, they get a boost. If they were strong in a caption that was worth more, then they get weighted down a bit.

Right now, it looks like this will only apply to a few of the competitors. You can see which shows are winning here. In short, Academie Musicale, Freelancers, Les Etoiles, Sky Ryders, Star of Indiana, and Velvet Knights only have eligible shows from the 1990s, so their scores will need to be coerced regardless of how the vote turns out. A few other corps, like Boston Crusaders, have shows from the 1990s that could win the vote as well, although I don’t think it’s likely.

But there’s still more time to vote! Voting closes tomorrow (June 28th) at midnight, so go vote while you still can, and I look forward to starting the Drum Corona International simulation soon!

Support

I hope you are enjoying Drum Corona International! People who do open-source projects like this often ask for donations to help cover expenses (like server costs) but luckily I’ve got that covered. Instead, if you’re enjoying any of my projects, please consider donating to the Michigan Drum Corps Scholarship Fund.

The Michigan Drum Corps Scholarship Fund is a 501(c)3 nonprofit that I cofounded to help support members of the Michigan band community who are interested in DCI. The organization offers scholarships to Michigan students marching or auditioning with any DCI drum corps. The economic implications of COVID-19 are broad, and I think scholarships programs like this are especially important for keeping drum corps accessible to everyone. Every dollar helps!



  1. For example, GE used to have subcaptions of Music Effect and Visual Effect, and there’s been lots of changes to sizes of judging panels and the roles of the judges themselves. This is especially true of percussion judging.↩︎

  2. The Central Limit Theorem implies this is for the better.↩︎

  3. I would be remiss if I didn’t say that these sheets complete shafted color guards. It’s another in a long line of examples that show DCI consistently fails to treat color guards with the respect they deserve.↩︎

Drum Corona International Week in Review: July 11

July 11, 2020
drum-corona-international drum-corona-week-in-review

Drum Corona Spotlight: California Nostalgia

July 10, 2020
drum-corona-international drum-corona-spotlight

Drum Corona Spotlight: North of the Border

July 7, 2020
drum-corona-international drum-corona-spotlight