[computer-go] Transformation between KGS ratings and Elo

[Alain Baeckeroot]

Le vendredi 1 février 2008, Andy a écrit :
> See below I created a table that shows the transformation from KGS ratings
> to the Elo that CGOS uses.  I set 6k=1800 because I believe that is what GNU
> 3.7.10 is under both systems.  Does anyone have more data points for bots
> that play on both systems?
> 
> Also is there an "all times" list for 19x19?  CS-9-17-2CPU is on top at
> 2297, but I don't think that's the strongest CrazyStone.  I think other strong
> 19x19 bots are not on the current list either.
> 
> To create the table I calculated the probability for a player of rank X to
> upset a player of rank X+1.  Then I converted this to the equivalent number
> of Elo points for the same upset rate.  Finally I made a running total,
> setting 6k to 1800.  The transform could be done using calculus I suppose
> but it's been a long time since I did that!  :)
> 
> 
>                ELO      set
> rank     k    1 rank  6k=1800
>  10k   0.80    139     1,244
>   9k   0.80    139     1,383
>   8k   0.80    139     1,522
>   7k   0.80    139     1,661
>   6k   0.80    139     1,800
>   5k   0.80    139     1,939
>   4k   0.88    153     2,078
>   3k   0.97    168     2,231
>   2k   1.05    182     2,399
>   1k   1.13    197     2,582
>   1d   1.22    211     2,779
>   2d   1.30    226     2,990
>   3d   1.30    226     3,216
>   4d   1.30    226     3,442
>   5d   1.30    226     3,667
>   6d   1.30    226     3,893
>   7d   1.30    226     4,119
>   8d   1.30    226     4,345
>   9d   1.30    226     4,571
> 

1800 is gnugo, so this puts top programs near 1k (2d for extreme
mogo_18) this seems reasonable to me.

Im surprised when i compare this scale to
http://en.wikipedia.org/wiki/Go_ranks_and_ratings

Obviously there is a factor 2 between both ratings scales, (as i don't
believe mogo_18 is 9d EGF ;), but this is just not important, as far
as we know it.
Alain