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Unread 11-04-2016, 10:45
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Re: Quick OPR Question

Quote:
Originally Posted by JewishDan18 View Post
Here's a link to the raw data (each row is an alliance)
OK:

Your "Teams" tab has data for only 44 alliances, which would generate 44 linear equations.

But you have 64 teams.

So you have more unknowns (Team OPRs) than equations.

So the linear system is underdetermined, and has no unique solution. There are an infinite number of solutions.

There are at least three ways you could deal with this.
1) Wait until you have enough data so you have an overdetermined system and there is a unique least-squares solution

2) Solve the system using the Moore-Penrose pseudo-inverse: x=pinv(A)*b. This will select the solution x which has minimum ||x||

3) Just compute each team's average (instead of OPR) until you have enough data: if a team played on L alliances, sum those alliance scores and divide the sum by 3L.

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