Komi assignment question

When I post a custom game I leave handicap at none, komi at automatic, and color at automatic. I also limit opponents to one lower and 2 higher. I’m currently 9k so this means 7k - 10k. From my understanding this should mean:

  1. No handi stones regardless of rank of opponent.
  2. If one rank lower accepts the challenge then my opponent gets black and I get white with no komi.
  3. If we are the same rank then color is random and white gets 7.5 komi.
  4. If my opponent is stronger then I get black with no handi and my opponent gets white with no komi.

But this is what is actually happening:

  1. Sometimes I get white with 6.5 komi when my opponent is stronger. Even 2 ranks stronger.
  2. When a stronger opponent gets white they are also given 6.5 komi. So if I play a 7k at my current 9k rank my opponent will get white with 6.5 komi.

Neither of these situations seems correct. I know OGS keeps ranks by points and tenths of a rank, but I don’t understand how the above situations could be correct.

Any insights on this would be appreciated. Thanks.

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When Handicap is off and komi is automatic, the komi is determined by the ruleset and board size. Perhaps turning on automatic handicap and restricting ranks in the same way you currently are is what you’re looking for?

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I think like @Samraku for the komi.
the point which surprise me is that you can get white against a stronger player and reverse, that’s not the behavior i expect with automatic colors ?

I always set colors to random or black or white, even when setting up a handicap game, so I’m not sure. The only time I’d use automatic is in setting up an open challenge with handicap, but I don’t generally play handicap games unless they’re arranged beforehand, and I thus know the amount of the handicap and which color I’ll be playing.

That can happen with ladder challenges as well sometimes

My settings are Japanese rules, handicap none, color automatic, komi automatic. To me “automatic” means OGS determines the proper setting for the two opponents. So the stronger opponent gets white, or it’s randomized for equal rank opponents. It doesn’t make sense that the stronger opponent gets black unless the two players arrange it that way. I don’t know the fine details about different rulesets, other than how the board is scored, but I assume komi is only applied with two equal rank players to offset the advantage when black goes first. As I said, having a player 2 ranks stronger than you getting 6.5 komi when you’ve given up your 2 handi stones just doesn’t seem correct. Maybe there is an issue with this particular settings configuration.

The komi is not illogical if you put no handicap.
The komi is to compensate the disavantage that black play first in a game with no handicap. So automatic means according to the rules which are made for a game without handicap between two players of same level (If they are or not is irrelevant)

Note that a game with no komi is the same as a game with one stone handicap.

Still the behavior of automatic color is illogical.
Are you sure you selected automatic, and not random color? I mean it happens often, when I checked similar posts on the forum.
If you are sure, you can try to replicate the bug so that it can be solved. Screenshots appreciated :blush:

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Color automatic randomized the color in the past if both players are within 1 rank, otherwise the stranger player got white.


Btw.: For 0 handicap, standard handicap games there is no “logical” way (I know of) to assign colors. The first play advantage is compensated is compensated by komi.

My expectation is color automatic = color random if handicap 0 and standard komi.

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So if I’m understanding this correctly, when you set handi to 0 then OGS assumes you’re asking for an even game as though both players had the same rank. So color gets assigned randomly (based on automatic setting) and komi is then given to whichever player is assigned white. This would account for the behavior I’ve seen.

I guess I disagree with the assumption that no handi should be interpreted as an evenly matched game. If I, as the weaker player, decide to play a stronger player with no handi (for whatever reason) I still expect to play black and the stronger player not given any komi. This seems to be the more reasonable and fairer way of doing things. I suppose you could set komi to custom and give it 0, but that would “cheat” the white player in a game where both players have the same rank.

I think the developers need to make the assignment of colors and komi a little more nuanced and not just assume equal ranks when posting a no handi game request.

Then you want handicap of 1, not 0.

Handicap of 1 means weaker player is black and white has 0.5 komi

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I’ve never seen anyone given a handi of 1 stone. For two same rank players going first as black is seen as a half stone advantage and so a half stone komi (6.5 or 7.5) is given to the white player. For two players one rank apart the 1 stone advantage is obtained by giving the weaker player black and going first and giving 0.5 komi to the stronger player to break any ties. This is how it’s stated in the AGA rules. It’s also the case that the weaker player is always given black.

What it comes down to is that setting handi to none, color auto, and komi auto should result in 1) the weaker player getting black and the stronger player getting white with 0.5 komi to break ties. In the case of same ranked players color is random and the player getting white is given 6.5 or 7.5 komi to compensate for going second.

This does not seem to be the way OGS is working.

“1 stone advantage” means “1 stone handicap”

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So your argument is “0 should be 1 and 1 shouldn’t exist”?

a) You choose Japanese, not AGA rules, so AGA wouldn’t apply at all.
b) The AGA rules state:

  1. Compensation: In an ever (non-handicap) game, Black gives White 7½ points for the advantage of the first move. […] In handicap games, Black gives White ½ point compensation. This avoids draws.

  2. Handicaps: The game may be played with a handicap to compensate for differences in player strengths. The weaker player takes Black, and either moves first, giving only ½ point compensation to White, as in Rule 3 (this is known as a “one stone handicap”), or places from 2 to 9 stones on the board before the first white move.

So it worked still as to expect.

Handicap 0 is no handicap, and handicap 1 reduced komi.
The stronger player takes always White only if handicap is used (handicap ≠ 0)


Please don’t say

If you cannot quote the rules text.

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Having looked at the Japanese and Chinese rulesets it seems neither really addresses the issue of handicap games. So I guess I should put AGA as the ruleset in my game request settings and see what happens.

This is a presentation of the rules from someone who adapted these from someone else who wrote them from the official associations. If you are so interested you could go find the original ones. R Jasiek did a lot of work and studies on rules, you can get some of his writing in the go rec group for example.
Considering handicap its implementation on OGS using chinese or japanese rules is similar to AGA, so you don’t have to restrain yourself to AGA rules.
There is a concern still between both rules to give the same result about the handicap stones being integrated in the scoring under chinese rules which is an advantage more for black but i let you think on it :wink:

Good research and lecture to you.

Picking AGA alone won’t solve your problem though.

Whatever the ruleset, if you opt for no handicap then of course there will be no handicap, meaning an even game (regardless of the players rank).

As others have pointed out, what you are looking for seems to be a level 1 handicap (i.e. stronger player takes white with 0.5 komi).

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