FRC Spyder

[Stayskull]

What does DPR and CCWM mean or represent?

[Mike Soukup]

Originally Posted by Stayskull

What does DPR and CCWM mean or represent?

The Android app shows this blurb when you tap the '?' button at the top of the stats page; I'm not sure about iOS:

OPR (Offensive Power Rating) uses a mathematical model to estimate each team's contribution to their alliances' scores. Higher is better.

DPR (Defensive Power Rating) uses the same mathematical model to estimate each team's contribution to the opposing alliances' scores. Lower is better.

CCWM (Calculated Contribution to Win Margin) = OPR - DPR. A team's total contribution to their alliances. Higher is better.

The usefulness of these statistics varies by game; some years it's accurate, some years it's a novelty. It's up to you to decide how to interpret them.

[Citrus Dad]

DPR (Defensive Power Rating) uses the same mathematical model to estimate THE AVERAGE SCORE OF the opposing alliances' scores. WHETHER LOWER OR HIGHER DEPENDS LARGELY ON THE CHARACTERISTICS OF THE OPPOSING TEAMS IN THOSE ALLIANCES.

[Trying to Help]

What a truly wonderful reason for unlimited data! Thank you for this app! Our team used it a ton today.

[Storcky]

The new Android version of the app requires Google Play Services... any chance of a BB10 friendly version? (although demand is not likely very high)

Thanks for all the work you do on this app!

[Mike Soukup]

Originally Posted by Storcky

The new Android version of the app requires Google Play Services... any chance of a BB10 friendly version? (although demand is not likely very high)

Google Play Services isn't actually required; it's only used to receive match score notices. The app should function correctly without it. I'll see if I can change the popup to only appear once so you don't have to dismiss it every time you open the app.

[XaulZan11]

Is it just more or are the rankings on Spyder not sorted by ranking points?

Got excited that 1675 was in 1st when they are actually in second.

[rwood359]

Originally Posted by XaulZan11

Is it just more or are the rankings on Spyder not sorted by ranking points?

Most things seem to be confused. I looked at one team that had played two matches with 60 something points in each match that had an OPR of 120. Another team with 2-1 record had -30 OPR.
Predictions are generating negative scores.

[Dave Flowerday]

Originally Posted by XaulZan11

Is it just more or are the rankings on Spyder not sorted by ranking points?

Sorry about that. It looks like this was caused by a defect in FIRST's API where they are not handling the If-Modified-Since header correctly. I disabled that header and now things are looking correct again - please let me know if you see further issues.

Originally Posted by rwood359

Predictions are generating negative scores.

Predictions probably weren't right for a while there due to the above problem, but negative scores in the predictions aren't an indicator of any issue. Predictions are based on summing each team's OPR which means the predicted score can go negative when a team has a negative OPR.

[BBray_T1296]

Negative or massive OPRs (and other ratings) are just the result of not enough data. In a statistic model with up to 60 variables (teams), It takes many data points (matches) before a useful solution is available.

In short: wait a dozen matches or so

[Ether]

Originally Posted by BBray_T1296

Negative ... OPRs are just the result of not enough data.

Not necessarily. If a team is really struggling, the OPR at the end of the event can be negative. There was a team with negative 10 OPR in Week1.

[BBray_T1296]

Originally Posted by Ether

Not necessarily. If a team is really struggling, the OPR at the end of the event can be negative. There was a team with negative 10 OPR in Week1.

You are right, if a team averages more penalties (In fouls or playing defense on their own teammates) then a negative rating can occur.