[wgardner]

And just to make sure I'm being clear (because I fear that I may not be):

Let's say that team 1234 played in a tournament and was involved in matches 5, 16, 28, 39, 51, and 70.

You compute team 1234's OPR using all matches except match 5. Say it's 55.
Then you compute team 1234's OPR using all matches except match 16. Say it's 60.
Keep repeating this, removing each of that team's matches, which will give you 6 different OPR numbers. Let's say that they're 55, 60, 50, 44, 61, and 53. Then you can compute the standard deviation of those 6 numbers to give you a confidence on what team 1234's OPR is.

Of course, you can do this for every team in the tournament and get team-specific OPR standard deviations and an overall tournament OPR standard deviation.

Team 1234 may have a large standard deviation (because maybe 1/3 of the time they always knock over a stack in the last second) while team 5678 may have a small standard deviation (because they always contribute the exactly same point value to their alliance's final score).

And hopefully the standard deviations will be lower in tournaments with more matches per team because you have more data points to average.