Quote:
Originally Posted by dodar
So OPR is how many points you scored?
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Basically, yes... OPR (Offensive Power Rating) is an approximation at how many points your team scores in the average match. Since the co-op bridge doesn't provide any points, it's not included, even though it's a testament to the value of your robot.
Quote:
Originally Posted by dodar
How is the OPR calculated this year?
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OPR is calculated the same way every year... I am a little fuzzy on the details, but basically OPR is found using Matrix & Linear Algebra to quickly solve a complex set of simultaneous equations that yields teams' average contribution in points.
I believe two equations exist for each match, one for the red alliance (A + B + C = X) and one for the blue alliance (D + E + F = Y)... in which A, B, C, D, E, and F are the teams on each alliance and X and Y are the match scores. If A and D competed with each other in a later match, two more equations might exist: A + D + G = R and H + I + J = S. I believe these equations are then approximated incrementally until values are determined for each team.
That's all a combination of speculation and secondhand information, but regardless, each team is treated as a constant for an entire competition. If you start out very poorly, then become very good, there's no telling what OPR you'll end up with!
Quote:
Originally Posted by Tetraman
That's why I find this OPR really odd. I mean, I can get why 1126 is low, because like your team had scores of 0, 3, 12 and so on, you also had a 50 with 340, and the matches you had with us were mostly in the high 30s and 40s, where your robot scored the majority of those points.
It's a system that's over my head is all.
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OPR would work perfectly if all robots performed perfectly consistently... If Robot A always scored 26 points, Robot B always scored 2, Robot C always scored 16, etc.... The primary reason why OPR is flawed is because it has to approximate the average number of points robots score, and that obviously is non-constant! Teams like 1126 at FLR this year (who improve over the course of an event) are generally underestimated by OPR because their offensive contribution changes so much.
Additionally, most OPR calculations (OPRnet included) don't include elimination matches... I think partially because the alliances are the same for each match, making them far less useful in terms of calculating OPR. Again, this is speculation, not the result of comparing OPR calculations of the same event that exclude and include elim matches.
For any seeking to learn a bit more about OPR, I recommend Ed Law's explanation for how it works... His statistic CCWM is calculated the same way as OPR, but looks at the winning (or losing) margin instead of alliance score. See:
http://www.chiefdelphi.com/media/papers/2174?
Nathan