Quote:
Originally Posted by Ether
I'd like to hear from anyone who has successfully computed World OPR using R.
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I'm intrigued. I'm relatively new to FIRST, so bear with me. OPR refers to offensive power rating, correct? You're referring to using the Choleski decomposition to produce an estimate of how many points any single team should be expected to contribute to an alliance score, based on past performance?
There's an R package that supposedly does this -- it's called optR and it's available on the CRAN repository. It has a function called choleskilm that should do the trick. Of course the raw data has to be shaped into a positive definite matrix first.
The size of the matrix could be a problem. The description that I found on this method for calculating OPR focused on using this method for data from a single competition -- generally no more than a 100 x 100 matrix. But 2700 x 2700? I'll experiment with smaller data sets over the weekend and see if I can figure out what the computation time will be.