OPR after Week Two Events

[Chris is me]

Originally Posted by Ed Law

The OPR is a good representation of how good a team is this year. Without this coopertition award and coopertition points and weird ranking system, every team is trying to score as much as possible. However for regionals with lots of teams and not that many matches, there is still a lot of luck of the draw and the ranking will become meaningless. In that case, the OPR will still tell the truth about a team because data does not lie, only people do.

I did a little work after comparing to our actual scouting data, and it seemed while teams like ours had a reasonably accurate OPR, it's really easy for one's OPR to balloon this year, so in a regional ranking sense it's less accurate overall. Technical fouls and fouls aren't removed from the data. Teams that have a playstyle that draws fouls, or just played worse opponents, get an advantage in OPR.

At WPI, a few teams happened to have their non-functional matches paired with other good teams, and OPR doesn't really know how to separate that out. Additionally, defense is huge this year, making this game less separable than other games. So while our average contribution to a match might be close to our OPR, other teams were a ways off in one direction or the other due to scheduling oddities or hella technical fouls.

[Basel A]

Originally Posted by Siri

If the information is available by match (which I'm not sure it is), does it inherently increase accuracy? The only DQ I've seen so is from G27. Not that DQs are common in any sense, but a robot that G27s could well have been a major contributor to the match score. (We were once red carded at an off-season when our robot went haywire at the end of a match we'd helped win.)

This scoring contribution is not true of other potential DQs, for instance the entire team no-showing or playing without clearing inspection, but it does apply for some. It could work if you had Disable information or no-show robots (vs 5.5.6 no show teams), but DQ might be a wash this year.

Sorry, I meant to refer specifically to no-show DQs (which were specifically mentioned by the previous poster). I don't think there's match-by-match information on DQs, let alone reason-for-DQ information.. Basically, you're right.


As for how well OPR is doing, the metric I typically use is % qualifying matches predicted correctly. I have 2013 OPR nearly 1% ahead of 2012 this time last year (81.5% vs. 80.6%), though the result isn't statistically significant (fwiw, p=0.29).

[marccenter]

BaselA,

So do you sum the 3 team alliance OPR scores and then use the highest value to predict the match winner?

[Basel A]

Originally Posted by marccenter

BaselA,

So do you sum the 3 team alliance OPR scores and then use the highest value to predict the match winner?

Yes. There are some problems with this method (e.g. in 2011, when 3 teams with great minibots were on an alliance), but I don't think there's a better way to do it.

Also, just for fun, 2012 OPR (used teams' average of all event OPRs, but they're all pretty similar) is predicting 2013 matches at about 61% (counting any rookies as OPR = 0). Thanks to Ed for the OPRs and Ether for the Twitter Match Data. Not sure what I'd do without you two.

Edit: I don't want to post too many times, but there's a couple different things here. One is OPR as a tool to predict what will happen. Ed's reply below is pretty much exactly what I do for predicting matches (except realtime OPR; that's something I'd like to do in the future). In this case, I'm talking about how well OPR evaluates teams this year vs. other years, for which I used post-event OPRs. You can't hit 80% predicting matches without realtime data.

[Ed Law]

Originally Posted by marccenter

BaselA,

So do you sum the 3 team alliance OPR scores and then use the highest value to predict the match winner?

I actually use a few ways to predict match results. When there are sufficient data like in Week 5-7 and World Championship, I use historical World OPR and highest OPR. I also use the OPR calculated in real time for that event. Using one of them, I predict the rest of the matches and predict the final ranking. It is useful to have some idea ahead of time.

[MisterG]

Great work as usual, very helpful data.

Does anyone have an update on when Northern Lights data may be available?

Lots of teams from NL are coming to WI next week.

[Citrus Dad]

Here's an interesting result: 294 has an OPR of 18.4 at the Central Valley. Yet it had no shooter so no auto or teleop points, and it couldn't hang. It had very strong defense (which put it very high on our #3 draft list--we picked 295, a strong defender as well instead). So something weird is happening the OPR if a team with no apparent offense is doing this well. Looks like the OPR this year is capturing defensive efforts as well.

[Cory]

Originally Posted by Citrus Dad

Here's an interesting result: 294 has an OPR of 18.4 at the Central Valley. Yet it had no shooter so no auto or teleop points, and it couldn't hang. It had very strong defense (which put it very high on our #3 draft list--we picked 295, a strong defender as well instead). So something weird is happening the OPR if a team with no apparent offense is doing this well. Looks like the OPR this year is capturing defensive efforts as well.

All data is alliance wide, not robot specific.

This is why you can't rely on OPR as your only source of data.

[AdamHeard]

Originally Posted by Citrus Dad

Here's an interesting result: 294 has an OPR of 18.4 at the Central Valley. Yet it had no shooter so no auto or teleop points, and it couldn't hang. It had very strong defense (which put it very high on our #3 draft list--we picked 295, a strong defender as well instead). So something weird is happening the OPR if a team with no apparent offense is doing this well. Looks like the OPR this year is capturing defensive efforts as well.

They didn't score much, but they did score. We had them averaging .2 in auto with a max of 2, and 1.64 frisbees in teleop with a max of 4.

[bardd]

When will Israel's rankings be updated?

[Taylor]

Originally Posted by Chris is me

I did a little work after comparing to our actual scouting data, and it seemed while teams like ours had a reasonably accurate OPR, it's really easy for one's OPR to balloon this year, so in a regional ranking sense it's less accurate overall. Technical fouls and fouls aren't removed from the data. Teams that have a playstyle that draws fouls, or just played worse opponents, get an advantage in OPR.

(bolded for emphasis)
I don't follow your logic. Teams that score points by drawing fouls are still teams that score points, and points = offense.