I think mean mu is a good starting point, but I think it can be improved. I think it can be adjusted for the mean mu of the races involved. Since new coach race calculations are relatively few compared to ongoing calculations, I think a little more overhead can achieve a slightly better result. I think you could create a delta for each previous race compared to the average of all coaches that have used that race. The average of this delta could then be used to adjust the average of all coaches for the new race.
mubo wrote:I figure since you've never played tournament Khemri, and you have played tournament orcs, we can't have a better idea of your Khemri ability than your orc ability. Which I think is fair? Happy to listen to sensible petition on this point though.
I agree that the khemri estimate can not be more accurate than the orc estimate, but does that justify saying that it isn't worse? I would probably start new teams at the initial phi regardless, only adjusting new mu away from average.
I love the Glicko system and I think it is a definite improvement, but I'm curious why you chose to use decay. Why does a coach not playing prove that their estimate is less significant? In physical sports this makes more sense. We don't know if the player is training as consistently etc. For more mental contests, I would argue that the decay is much less significant. I know for leaderboards it is important to have a high decay to keep positions temporary, but to me this environment does not argue for a middle choice.
Why chose 100 phi as the cutoff? The description from the NAF overview page says "it will usually take a couple of tournaments with a race before phi drops below 100, and we become confident enough of ability to provide a rank." One of my own races has played 7 tournaments over 4 years and is considered inactive. To me, that does not appear to be working as intended based on the description. Maybe it is, maybe it's the decay, maybe my opponents had a high mu. It just seems odd to me. Is there a theoretical reason for 100 being the cutoff?
Thank you for doing this!!! I'm really just being picky with my above statements. I think what you did is great.
Edited a mu to phi typo.