In the past we’ve used the OPR/DPR concepts to allow us to find those teams who may or may not be accurately placed in the rankings for Elimination round selections.
What are your thoughts regarding Breakaway, is OPR/DPR something that makes sense with the new seeding and coopertition points?
As I told my team this morning, this competition has two distinct game strategies:
In the qualification rounds, then the strategy will be driven by the possible seeding points. So a strong alliance may actually do most of the scoring for the other alliance, to boast their coopertition bonus. As I told them, in the closing seconds of the game, and you are comfortably ahead and have a chance to take a shot, where do you shoot - your goal or their goal? Answer, their goal, for 2 bonus points, rather than the 1 seeding point you would get from shooting into your own goal.
In the elimination rounds, score, score, score/defend, defend, defend.
So from a scouting perspective, how do we find those teams’ true OPR? Can we even determine the DPR with this game, since teams may choose in qualification rounds to not even have defense?
At this point, my team scouting strategy regarding scoring potential is:
Goals (for either alliance)
Assists (balls passed to alliance partner, which is then scored)
If each alliance plays the game in a “standard” fashion (i.e. both teams attempt to win), I think that OPR/DPR will work fine. However, anything goes away from that will mess up the meaning of the values. Because OPR/DPR just goes by final score, it does not necessarily give credit to who scored, and sometimes can give undue credit because of an arranged match.
Quite honestly, there’s not “automatic” way to scout this year that will necessarily be accurate due to the fact of how long the “collusion” argument is. What I mean by this is that you can’t just run a program that grabs values off usfirst.org and calculates OPR/DPR and think that it’s accurate.
I’d say measure the team’s performance in normal matches and throw out any colluded ones (this may or may not include ones in which they attempt to make the score more even). It’s difficult to tell. In the end, the numbers won’t tell you everything. Write downn general impressions to help you.
I agree, we don’t do automatic scouting. I have used the OPR values to look for those “diamonds in the rough” that we may have missed through our scouting. OPR values were only a very small part of what look at though.
Okay, I’ll be the totally confused one, what do OPR and DPR stand for?
I get what you’re saying (the full force of the Coopertition point bonuses finally hit our strategy team about an hour ago), though. Scouting this year is going to be really tough, and we decided that we weren’t even going to think about how we’re going to do it this year until AFTER the robot is done.
OPR = Offensive Power Ranking. High number means you have a good offensive robot. DPR = Defensive Power Ranking. High number means you have a poor defensive robot.
My team, as well, was pretty stunned by what the seeding and coopertition concepts mean! Should be fun!
I’ve tried to make the below somewhat tactful, but I can’t find the words, so I apologize for the offense it may cause.
It’s my opinion that OPR was never a substitute for actual scouting to begin with. No team I ever work with will ever perform to make our OPR better, as teams picking based only on OPR won’t be forming cohesive alliances that work well together as a unit.
In Lunacy, OPR basically was as good as flipping a coin, or averaging a team’s score. People have told me Overdrive was better though. This year in particular, OPR would be a disaster, because there’s more than one task.
So yeah. Watch a team and how they play. If they score for the opponent, count those with your scouting as if they scored on themselves.
I agree with your comments regarding Lunacy. We have a very formal and extensive scouting program. We had some limited success with highlighting teams based on OPR in the past (as a way of trying to find out teams that were less than successful in the W/L column, mainly due to strength of schedule issues.), but it was never the main part of our program.
To many teams, I believe, look for that easy way of scouting, when it is hard work and determination that will really pay out the rewards.
My main question in this thread is two-fold …
Does anyone see any use of OPR or DPR this year? If so, how?
Other than the items that I intend on scouting (for scoring in matches), as seen in the first post, do you all see other things that should be tracked, watched, or calculated?
As a guy that wrote lots of OPR stuff last year, I’ll chime in.
OPR should never be used as the only scouting mechanism. It can help point out potential diamonds in the rough, as a team with a very high OPR probably has it for a reason. It can usually predict fairly well the teams that actually get into eliminations, but not a whole lot better than simply looking at the rankings.
OPR worked very well in 2008 because 2008 was a very robot-centred game with very little defense. Since there was little active defense, it was possible to score approximately the same amount of points every time you went out, which made the algorithm work better. It worked less well in 2009 because of the immense contribution (up to 50% from some scouting estimates I’ve heard) of human players, and the very heavy defense in the game. A robot might score 50 points one round, then 10 the next because they were pinned the whole match. 2007 was not an OPR year because of the exponential nature of the scoring. If your presence adds 5 points through whatever mechanism to the expected score of each alliance you’re on, then your OPR will be 5.
Does anyone see any use of OPR or DPR this year? If so, how?
I think it should still be accurate. If your robot contributes points on average to the alliance it is on (whether by feeding balls to the next zone, scoring balls, hanging each time, or even just having a good strategy), then your OPR will be higher. Since the scores are linear and human players have very little to do with it, it should be more “accurate” than 2009.
That said, I reiterate that it is nothing more than the solving of a system of equations. It is just a slightly different way of looking at the scores that teams put up to try and find robots that may have just been unlucky with their teammates or opponents. If a robot is a feeder bot and you’re a scorer bot, then the feeder bot will probably be a better choice than a scorer bot with a higher OPR.
To comment on the seeding setup:
-I think only extremely confident teams will be scoring for their opponents, so it shouldn’t affect things too much. The very top teams will probably have OPRs lower than theoretically possible because they’ll be scoring for their opponents slightly. This will slightly raise the OPRs of low-performance teams, but not too much because the elite teams’ scoring-against will be spread across all of their opponents, and will only occur in matches that are turning out to be blowouts.
Actually Offensive/Defensive Power Rating IIRC. The OPR by itself (for a single team) does not give you a ranking, but rather a rating of how much it theoretically contributes to a team.
I agree that OPR shouldn’t be used as the only scouting mechanism. However, I still think that OPR’s accuracy is dependent on how often you see the shutout collusion (or an alliance shutting itself out on purpose), since that seems to have been the hot topic in strategy discussion. Every time somebody does one of these, it will skew the value of OPR for all six teams (too low on one side, too high on the other). As long as both teams are actually attempting to win, however, I agree that you probably won’t see much scoring for the other alliance.
i think if FIRST still records W/L/T stats, RPI (Ratings Percentage Index) might actually be a better formula to use. If your looking for teams that had tough SoS’s (Strength of Schedule). Then this is something that should be looked into
after al, OPR will drastically change once the eliminations begin because of the sudden rise in defensive play.
The formula for RPI is as follows
RPI = (WP * .25) + (OWP * .50) + (OOWP * .25)
Where WP is Winning Percentage, OWP is Opponents’ Winning Percentage and OOWP is Opponents’ Opponents’ Winning Percentage.
Scoring for opponents will probably be quite common, given the complete shakeup of last year’s rankings. A team that was 15-1-0 at the Waterloo regional last year dropped to dead last in the rankings. So that will depress top teams’ OPRs since they’ll spend some of their time scoring against themselves, and slightly elevate lower-performing teams’ OPRs since they’ll be getting some help scoring.
Now I’m a bit confused; this post shows that the new seeding algorithm keeps the ranking order more or less the same (using last years data). The post you linked shows a completely different result.
You are looking at two different sets of scores, but regardless, I think you still can see the same thing in each. Here are two cases:
Curie 2009
– Team 668 was in 44th place. According to the new seeding, they are now in 3rd.
Newton 2009
– Team 1629 was in 8th place. According to the new seeding, they are now in 22nd.
Those are huge changes, as how they impact the teams. If you had team that totally dominated before, 75-0, for example, that team doesn’t do any better than the teams they just beat, and perhaps if there had been a penalty - they would actually do worse than the teams they just beat.
Let’s see if we can get this cleared up a bit. I believe that in Andrew’s calculation he kept the seeding scores and the coopertition bonus separate, but I’m not sure. If that is indeed the case, that’s where the two differ as I have the coopertition bonus added to the seeding scores in mine.
I could be missing something, since I don’t have much time to read the manuals (college and all), but don’t ranking points COME BEFORE the coopertition points?
In games where you have a difference of 7 points, no problem over here, go get like 4 more goals to even it up, or even more if it seems possible that the opponents will not be able to turn the tide somehow from this move. You’d do that do add coopertition points to make sure you will be ranked first in you rank level (if someone else is 2nd place with you, your coopertition points will beat his, therefore you’ll be above him in ranking). But if you are about 1-2 in point difference, I’d say forget about it. MAKE SURE YOU WIN, because 2 ranking/seeding points are much more important that 2 coopertition points, as it always was!
As I see it, the coopertition is just a tie-breaker for similar ranks.
Please do correct me, for I am confused of the comments in this topic.
I understand that college, and such can keep you busy, but take 5 minutes and read in the Tournament section 9.3 (especially 9.3.3 - 9.3.5). Ranking points are no longer a part of the game. There is no 2 points for a win. Totally different formula and philosophy. Please do read the manuals for this game!
