2015 OPR After Week One Events

[Ed Law]

I think I misunderstood what the negative numbers mean. Now my understanding is these are regular surrogate teams just like in past years. FIRST is just using to minus sign to signal they are surrogate teams.

I have always included surrogate teams in calculating OPR. I assume all teams always try their best in every match whether they are a surrogate team or not. In the past, based on Match Results only, we don't know which team is a surrogate team unless you look at the match schedule. Now that we know which teams are surrogate, we can potentially not include them in the calculation. However, I propose for the sake of consistency to previous years, we will continue to calculate OPR the same way including surrogate teams in both the A matrix and b vector when solving A x = b.

For component OPR, I will need to study it some more to see if there is a benefit to not include surrogate teams. I already checked my program. It can be done relatively easily. It may improve the accuracy of the component OPRs. However the scale and shift operations I do to take care of surrogate and DQ teams seem to work well enough. By not including the surrogate teams, I still have to do the scale and shift for DQ teams. I have to do a little more testing before making a decision whether to change it or not.