Life In 19x19

mart900 wrote:Go tournaments, as far as I know, often have elimination brackets

I suppose it depends on which region and which go sub-population you're focusing on.
Elimination brackets in pro tournaments do seem to be more common nowadays than they were a couple of decades ago.
But most (amateur) EGF tournaments use McMahon with some additional tie-break scores (such as SOS and SODOS), which is perfectly capable of dealing with draws. And some EGF tournaments have indeed used integer komi in the past, like the London Open in the 90s (6 komi under Japanese rules IIRC).

tundra wrote:players might collude or conspire to engineer a draw, in order to split the game fee evenly between themselves.

I remember that in one of those London Open tournaments in the 90s, there was a controversy that 2 top players from Russia allegedly colluded to make a draw in the last round, which maximised their combined prize money. Perhaps a careful structuring of prize money might work to avoid such issues?

gennan wrote:McMahon with some additional tie-break scores (such as SOS and SODOS), which is perfectly capable of dealing with draws.

For no real purpose. Direct comparison, drawing lots, letting them play 5' SD or previous ratings would be the honest tiebreakers. However, money prizes can be shared easily so there is no need to break ties. I have never understood this determination to split hairs among equal performers and have sometimes suffered dearly when having beaten the tiebreak winner with the same MMS or Swiss score.

When it comes to determining the winnner of a McMahon tournament, a McMahon tournament would usually have a top group with a size that is suitable for the number of rounds (IIUC), so there is likely a unique player with the highest number of wins in the top group and tie-breakers aren't needed (at least for 1st place).

I don't know how often integer komi would thwart this, but I guess organisers could could still ignore tie-breakers and share prize money in such cases, if there is no time for an additional play-off to break ties and there isn't really a strong requirement to have a unique winner.

gennan wrote:When it comes to determining the winnner of a McMahon tournament, a McMahon tournament would usually have a top group with a size that is suitable for the number of rounds (IIUC), so there is likely a unique player with the highest number of wins in the top group and tie-breakers aren't needed (at least for 1st place).

We may wish. In practice, many German or European McMahon tournaments have 5 rounds to fit well into a weekend and the top group is chosen so that 6 rounds would be the most suitable (or in some very small tournaments, 4 rounds.) Many people, including me, like 5 rounds (although I would also like 6). It is just that the other conditions and tournament director / pairings manager do not necessarily enable a unique top scorer then.

RobertJasiek wrote:

luigi wrote:Under area scoring, 7 komi plus button is best and probably no less balanced than komi 7 without button. It's equivalent to territory scoring with 6.5 komi.

Different kinds of buttons have been suggested so you must specify your type.

I mean the standard button, which is the following, as far as I know:

The button is a special token which is placed next to the board at the start of the game. On your turn, if neither player has taken the button yet, you may not pass, but you may take the button instead of making a board play. At the end of the game, a half point is added to the score of the player who has taken the button. When checking for repetitions, two identical board positions are still considered different if the button had already been taken in one of them but not in the other.

In Swiss and McMahon tournaments, Pro-Rata Territory Scoring Fractional Komi should always be used up to the number of rounds there would be in a single elimination in the top group, and then all rounds after that should use area scoring with integer komi. In round robin the idea is consistent conditions for all games so it's not quite for round robin. However, in round robin you can do this: score each game with both Pro-Rata Territory Rules with Fractional Komi and area rules with integer komi, then sum the difference in score from both then divide by 2 to get the combined mean Territory-area score. It would basically be area scoring with territory points doubled and scored Pro-Rata, and then the overall score divided by two.

Elom0 wrote:Pro-Rata Territory Scoring Fractional Komi

What is Pro-Rata [...]?

score each game with both Pro-Rata Territory Rules with Fractional Komi and area rules with integer komi, then sum the difference in score from both then divide by 2 to get the combined mean Territory-area score.

This is no good because strategy differs for different scoring methods.

RobertJasiek wrote:

Elom0 wrote:Pro-Rata Territory Scoring Fractional Komi

What is Pro-Rata [...]?

It means dame is counted as territory for each side proportional to the number of

score each game with both Pro-Rata Territory Rules with Fractional Komi and area rules with integer komi, then sum the difference in score from both then divide by 2 to get the combined mean Territory-area score.

This is no good because strategy differs for different scoring methods.

It's exactly because strategy differs for different scoring methods that it is indeed excellent. I'm surprised, I didn't think you'd be one to promote dumbing things down, I thought you'd appreciate it with something like "Combining scoring methods makes the endgame more dynamic and fair and if each player is used to one scoring method, neither player will have advantage", or something, haha!

Elom0 wrote:

RobertJasiek wrote:

Elom0 wrote:Pro-Rata Territory Scoring Fractional Komi

What is Pro-Rata [...]?

It means dame is counted as territory for each side proportional to the number of

Proportional to the number of what?

If it is just "dame counted as territory for each side" and you mean that each dame stone scores for its player, then this is similar to AGA Rules without the rule of a pass stone for White's game ending pass, therefore, I suppose, creates pass-fights and hence is not suitable for practical play. If you think that pass-fights do not occur, prove their non-existence!

RobertJasiek wrote:

Elom0 wrote:

RobertJasiek wrote: What is Pro-Rata [...]?

It means dame is counted as territory for each side proportional to the number of

Proportional to the number of what?

If it is just "dame counted as territory for each side" and you mean that each dame stone scores for its player, then this is similar to AGA Rules without the rule of a pass stone for White's game ending pass, therefore, I suppose, creates pass-fights and hence is not suitable for practical play. If you think that pass-fights do not occur, prove their non-existence!

Sorry, my bad, proportional to the number of each colours stones surrounding tge dame. For example, if there are 3 points dame surrounded by 3 black stones and 5 white stones, black gets 1+(1/8) points and white gets 2+(7/8) points.