Rank And Handicap
How rank difference is traditionally used to determine the handicap
When a 6 kyu plays another 6 kyu, either player can take Black. Over several games, they would alternate. There should normally be no handicap and White would get komi to offset Black's advantage in moving first. When a 6 kyu plays a 5 kyu, the 6 kyu always is Black, and there is no komi (or only a half point to prevent jigo). So we say there is a one stone difference in the strength of a 6 kyu player and a 5 kyu player. When a 6 kyu plays a 4 kyu, it is a two stone difference in strength, so the 6 kyu not only takes Black, but puts two stones on the board before White makes a move. (0 or 0.5 point komi.)
6 kyu vs. 3 kyu, three handicap stones; up to 6 kyu vs. 1 kyu = five handicap stones; 6 kyu vs. 1 dan = six handicap stones; and so forth. In theory, a 20 kyu player should take a 19-stone handicap from a 1 kyu, and a 20-stone from a 1 dan. In practice, handicaps larger than 9 stones are rare. When the difference in strength between the players is greater than 9 stones, they usually just chalk it up as a Teaching Game, which is not to say that White will surely win the game. Alternatively, large amounts of komi can be given to Black.
This way of determining the handicap by rank difference is largely independent of the ranking system used. However, in tournaments, particularly when prize money is at stake, no handicap will be given to the weaker player. In more informal tournaments - as are most tournaments in the amateur Go world - a reduced handicap is often seen, in order to balance the interests of having an interesting game on one hand and not completely levelling differences in skill on the other hand.
Advantage for White
The traditional handicap scheme gives an advantage to White. In an even game, Black plays first and gives komi, which amounts to putting down one stone and give komi. If Black is one stone weaker, then he should take two stones and give komi. Or, reversing colors, White plays second and gives komi. If White is one stone weaker, then he should play first (i.e., play Black) and take komi. Either way, taking Black without receiving komi is an inadequate handicap for a one stone difference in strength. Similarly, taking 2 stones without receiving komi is inadequate for a 2-stone difference. And so on.
However, one should never lose sight of the purpose of handicaps, which is to make teaching games more interesting and instructive. Using a handicap system in tournaments may be questionable to begin with, so that the question of making it a fair system becomes irrelevant. That being said, a handicap system that is a little light provides a reasonable environment for the rapidly-improving player. The spacing between ranks is likely to be a more serious issue than this one of first-play advantage.
Alternatives
- Japanese Points Rating System
- Point Ranking Scheme At Tokyo Go clubs
- The Dutch class system
- Proper Handicap
- kadoban - not a ranking scheme, but a way to determine handicap for opponents who often meet each other.