gennan wrote:
I think go ranks have no meaning without handicap. Handicap defines ranks. If go had no handicap system and all games would be even games, we would just use an Elo rating system.
But the go rating systems all try to align winrates to handicaps.
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This puts a responsibility on go rating systems to convert well between ratings and ranks and to keep this conversion consistent in the long run. I do think the go rating systems are reasonably effective in this respect, but there is clearly room for improvement.
Back in the 1970s I devised a rating system for the New Mexico Go Association. The AGA had already devised an Elo system, but I took the handicap basis seriously and did not do so. OC, there was no theory at the time about how to base a rating system on handicaps (Is there one now?
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), so I drove by the seat of my pants.
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I divided ranks into two, so that a strong shodan would take White against a weak shodan, receiving ½ pt. komi, etc. Instead of complicating the calculation of ratings, I had each game count the same number of points, and increased the point range of each successive rank by 5%, going upwards. Since most of our players were in their 20s I added inflation points to the winners' scores. After three years, based upon the results of visiting players and of our players playing elsewhere, I promoted everybody by ½ rank and added more inflation points. Two years later I had no reason to change the system.
OC, such a system faces the problem of players who make very rapid progress at the SDK level and above. Other systems do, as well, but the very short ranges of ranks in the DDK range do not present much of an obstacle.
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Human intervention may be required. I might have done so for Janice Kim, but after her summer as a go student in Korea, she was cautioned not to play with amateurs. So that problem solved itself.
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