Is Komi standard play?

[jug]

If we want to determine what the win rate would be at 4.5 or 5.5 komi, I think the only valid way would be to generate a large sample of games played at 4.5 or 5.5 komi.

Here are some numbers from DGS (sample of ca. 83.000 finished 9x9 games) with counts, percentages of Black-win (BWin) and White-win (WWin) and Jigo (BWin & WWin are shown without Jigo; add half of Jigo-percentage if you want) for a variety of Komi. Time-Outs are not included and each game has at least 10 moves.

Code: Select all

| Komi | CNT   | BWin    | WWin    | Jigo   |
+------+-------+---------+---------+--------+
| -6.5 |   342 | 45.0292 | 54.9708 | 0.0000 | 
| -6.0 |   418 | 50.2392 | 48.3254 | 1.4354 | 
| -5.5 |   467 | 45.8244 | 54.1756 | 0.0000 | 
| -5.0 |   486 | 51.2346 | 47.1193 | 1.6461 | 
| -4.5 |   578 | 51.0381 | 48.9619 | 0.0000 | 
| -4.0 |   547 | 49.5430 | 47.8976 | 2.5594 | 
| -3.5 |   630 | 49.8413 | 50.1587 | 0.0000 | 
| -3.0 |   586 | 46.0751 | 51.3652 | 2.5597 | 
| -2.5 |   627 | 45.9330 | 54.0670 | 0.0000 | 
| -2.0 |   696 | 48.9943 | 48.7069 | 2.2989 | 
| -1.5 |   668 | 50.7485 | 49.2515 | 0.0000 | 
| -1.0 |   706 | 44.3343 | 52.9745 | 2.6912 | 
| -0.5 |   721 | 48.1276 | 51.8724 | 0.0000 | 
|  0.0 |  4305 | 47.4564 | 50.8711 | 1.6725 | 
|  0.5 | 17091 | 40.2785 | 59.7215 | 0.0000 | 
|  1.0 |   868 | 42.0507 | 55.2995 | 2.6498 | 
|  1.5 |  1192 | 49.6644 | 50.3356 | 0.0000 | 
|  2.0 |   953 | 42.2875 | 54.4596 | 3.2529 | 
|  2.5 |  1393 | 48.1694 | 51.8306 | 0.0000 | 
|  3.0 |  1016 | 44.7835 | 52.4606 | 2.7559 | 
|  3.5 |  2132 | 50.0469 | 49.9531 | 0.0000 | 
|  4.0 |  1195 | 45.1046 | 52.7197 | 2.1757 | 
|  4.5 |  1735 | 47.0317 | 52.9683 | 0.0000 | 
|  5.0 |  1487 | 45.9314 | 51.3786 | 2.6900 | 
|  5.5 |  2516 | 48.6089 | 51.3911 | 0.0000 | 
|  6.0 |  1589 | 47.8918 | 50.0315 | 2.0768 | 
|  6.5 | 28549 | 46.3414 | 53.6586 | 0.0000 | 
|  7.0 |  9039 | 46.0892 | 49.2422 | 4.6687 | 
|  7.5 |    68 | 48.5294 | 51.4706 | 0.0000 | 
+------+-------+---------+---------+--------+
| ALL  | 82732 | 45.4419 | 53.6443 | 0.9138 | 

The sample requires probably more restrictions as it seems White have a higher winning-percentage almost regardless of used komi

[Uberdude]

jug, presumably those komis are to handicap games between players of different strengths? What we need is win rates for different komi for games between players of equal strength. (Or different strength but random colour and a much larger sample to see the deviation fron 50%).

[Abyssinica]

A lot of people have higher win rates as white.

[Scurvodsky]

A lot of people have higher win rates as white.

Because the komi helps them or b/c the stronger player usually plays white?

[jug]

jug, presumably those komis are to handicap games between players of different strengths? What we need is win rates for different komi for games between players of equal strength. (Or different strength but random colour and a much larger sample to see the deviation fron 50%).

You are right, I didn't restrict the sample to even games. Here's a list from DGS with more restrictions:
* finished games
* more than 10 moves
* size 9x9
* no time-outs
* no handicap stones
* Rating-diff between Black and White <1.5k
* (rated and unrated games, no restriction on strength of players)

Code: Select all

| Komi | CNT   | BWin    | WWin    | Jigo   |
+------+-------+---------+---------+--------+
|  0.0 |   631 | 57.5277 | 41.5214 | 0.9509 | 
|  0.5 |  1132 | 59.6290 | 40.3710 | 0.0000 | 
|  1.5 |    88 | 51.1364 | 48.8636 | 0.0000 | 
|  2.5 |   123 | 60.9756 | 39.0244 | 0.0000 | 
|  3.0 |    23 | 52.1739 | 47.8261 | 0.0000 | 
|  3.5 |   342 | 56.7251 | 43.2749 | 0.0000 | 
|  4.0 |   716 | 47.4860 | 50.0000 | 2.5140 | 
|  4.5 |  1035 | 46.2802 | 53.7198 | 0.0000 | 
|  5.0 |   903 | 48.3942 | 49.3909 | 2.2148 | 
|  5.5 |  1290 | 46.8217 | 53.1783 | 0.0000 | 
|  6.0 |   992 | 46.0685 | 51.4113 | 2.5202 | 
|  6.5 | 10582 | 46.8626 | 53.1374 | 0.0000 | 
|  7.0 |  2472 | 45.1052 | 49.2314 | 5.6634 | 
|  7.5 |    24 | 45.8333 | 54.1667 | 0.0000 | 
+------+-------+---------+---------+--------+
| ALL  | 20389 | 47.9965 | 50.9736 | 1.0300 | 

the query is only for me for reproducing the sample: select Komi, count(*) as CNT, sum(if(Score<0,1,0))/count(*)*100 as BWin, sum(if(Score>0,1,0))/count(*)*100 as WWin, sum(if(Score=0,1,0))/count(*)*100 as Jigo from Games where Status='finished' and Size=9 and Score between -1500 and 1500 and Moves > 10 and Handicap=0 and Black_Start_Rating>-1000 and White_Start_Rating>-1000 and abs(Black_Start_Rating - White_Start_Rating) < 150 group by Komi with rollup having CNT > 20  ;

[Abyssinica]

A lot of people have higher win rates as white.

Because the komi helps them or b/c the stronger player usually plays white?

With any sort of handicap as white on kgs, komi = 0.5

[HermanHiddema]

@jug: How is it that you have data for all those different komi values? I can't imagine that a nigiri game has random komi, and if the values are as they are to compensate for strength difference, then the data is meaningless.

[emeraldemon]

@jug: How is it that you have data for all those different komi values? I can't imagine that a nigiri game has random komi, and if the values are as they are to compensate for strength difference, then the data is meaningless.

1) DGS has a "proper komi" option, which adjusts komi based on strength difference. I imagine this is where most of those games come from, and I agree those games don't answer the question.

2) DGS has a "fair komi" option, where players can bid on komi in a few different ways (open auction, secret auction, etc.). These could presumably be good indicators, I don't know how many games are played this way. I tried three myself, bid 8 or 8.5 to play black and won all three

3) Of course a player can just put a game in the waiting room with an unusual komi and see if anyone will take. I doubt this happens very often.

[jug]

@jug: How is it that you have data for all those different komi values? I can't imagine that a nigiri game has random komi, and if the values are as they are to compensate for strength difference, then the data is meaningless.

I didn't pay attention to what conditions the sample should fulfill to answer some question, but just provided some data because I can with access to the DGS-data.
But actually ... what was the question again? The above sample-data was only for 9x9 games, ... or are we talking about other board-sizes as well?

The 2nd post with numbers have a rating-diff-restriction, so the players are not more than 1.5kyu apart, but still the majority of games were indeed setup by conventional handicap (fix komi 6.5) or proper handicap taking the rating-diff into account (even though the smaller the board-size the less influence the rating-diff has).

emeraldemon is right about that DGS has this proper-handicap, but DGS also has a way for manual handicap/komi-setup (nigiri, choose black or white color, or start a double-game). However, I just checked and the number of games for the manual setups are probably too small (counts in range 20-100 with less komi-variety) to have some reliable sample-size.

2) DGS has a "fair komi" option, where players can bid on komi in a few different ways (open auction, secret auction, etc.). These could presumably be good indicators, I don't know how many games are played this way

There are ca. 300 finished DGS-games that used fair-komi for game-setup, but the majority was for 19x19.

3) Of course a player can just put a game in the waiting room with an unusual komi and see if anyone will take. I doubt this happens very often.

If we are only talking about 9x9 games, then there are ca. 10.000 finished DGS-games that were started with a even-game with nigiri and manual komi, but the majority of those were using komi 6.5 or 7 (a lot of those games are the 9x9 ladder-tournament). If we would further restrict the games on the players-strength or max 1k-rating-diff it would be only 25% of those counts.

I'm not sure, if I can be helpful with providing DGS-data ... if it's clear what exactly the restrictions should look like, I may provide some data ... though in this case it doesn't sound like it

[coconut]

I hate komi. I don't think black has an advantage because it goes first. It's a turn based game, both black and white have equal opportunities to make their marks on the board. In the end it's about cleverness and strategy and not who goes first.

I also hate losing just because of Komi points.

I mean, I consider Komi just for tournaments and not a rule. It is a fairly new rule and it's different in every country. In Hikaru no Go, Sai the Go ghost has no idea what Komi is. He's thousands of years old and he knows how to play Go better than anyone alive, but Komi is new to him.

Kind of like how my dad plays backgammon where you have to get the exact number to bear it off every time, you can't start taking off the fours if you get a five and don't have any pieces on the fives or sixes. You have to get a four. He thinks it's a better way to play, and doesn't care that standard rules are different.

I have more fun with my dad's rules anyway.

My dad isn't playing backgammon at tournaments so it doesn't matter. Just for playing regular games for fun, or standard play, one of the rules, I can't consider Komi a real rule because it is a tournament addition.

[Elom]

I hate komi. I don't think black has an advantage because it goes first. It's a turn based game, both black and white have equal opportunities to make their marks on the board. In the end it's about cleverness and strategy and not who goes first.

I also hate losing just because of Komi points.

I mean, I consider Komi just for tournaments and not a rule. It is a fairly new rule and it's different in every country. In Hikaru no Go, Sai the Go ghost has no idea what Komi is. He's thousands of years old and he knows how to play Go better than anyone alive, but Komi is new to him.

Kind of like how my dad plays backgammon where you have to get the exact number to bear it off every time, you can't start taking off the fours if you get a five and don't have any pieces on the fives or sixes. You have to get a four. He thinks it's a better way to play, and doesn't care that standard rules are different.

I have more fun with my dad's rules anyway.

My dad isn't playing backgammon at tournaments so it doesn't matter. Just for playing regular games for fun, or standard play, one of the rules, I can't consider Komi a real rule because it is a tournament addition.

Well, the decision of komi was based on the games of top players. Black wins more games than white without komi. Near the komi used today (6.5 under territory scoring, 7.5 under area scoring) it's rather close to 50%. Bots seem to agree-you might want to have a look at this https://senseis.xmp.net/?HistoryOfKomi.
Something cool about the perhaps imperial stone system migrated towards Japanese martial arts is that if you group players 9 dan to 7 dan from the best or second best player in the world (9 dans within one stone (even game (with komi)), 8 dans within two stones (one stone handicap), and 7 dans within three stones (two stone handicap)), you get something similar to Michelin stars .

[Mike Novack]

I hate komi. I don't think black has an advantage because it goes first. It's a turn based game, both black and white have equal opportunities to make their marks on the board. In the end it's about cleverness and strategy and not who goes first.

It might help you understand if you considered a simpler "game".

simple chance based game --- A and B take turns flipping a coin. A goes first. As soon as a player gets a heads, the game is over and that player wins. Calculate the probability that A will win the game << hint -- A's chances of winning are GREATER than 50% >>

You want the game to be one of skill? Instead of flipping a coin, make that a task that depends on skill. Assume that the players are equally skilled and at that skill level they have a 50% chance of doing the task on any turn << say they are "shooting hoops" and each puts half of their foul shots into the basket >> What are A's chances of winning this game.

Now a (much) hared problem, but one that might get you to understand komi -- assume that A's skill level is such that 30% of his shots go in the basket. What must B's skill level be to have to be suach that B has an equal chance of winning << hint -- did you immediately see that when A's skill leve was such that 50% went in B would have to be 100%>>


Michael D Novack

[EdLee]

I hate komi. I don't think black has an advantage because it goes first.

$$B komi 0.0
$$ ---
$$ | . |
$$ ---

Click Here To Show Diagram Code

[go]$$B komi 0.0
$$ ---
$$ | . |
$$ ---[/go]

Tie ( both pass. )

$$B komi 0.0
$$ -------
$$ | . . |
$$ -------

Click Here To Show Diagram Code

[go]$$B komi 0.0
$$ -------
$$ | . . |
$$ -------[/go]

Tie ( both pass. )

$$B komi 0.0
$$ --------
$$ | . . . |
$$ | . 1 . |
$$ --------

Click Here To Show Diagram Code

[go]$$B komi 0.0
$$ --------
$$ | . . . |
$$ | . 1 . |
$$ --------[/go]

What happens if continues ?

$$B komi 0.0
$$ --------
$$ | . 2 4 |
$$ | 3 1 . |
$$ --------

Click Here To Show Diagram Code

[go]$$B komi 0.0
$$ --------
$$ | . 2 4 |
$$ | 3 1 . |
$$ --------[/go]

Is there a strategy that guarantees at least a tie ?

$$B komi 0.0
$$ --------
$$ | . . . |
$$ | . 1 . |
$$ | . . . |
$$ --------

Click Here To Show Diagram Code

[go]$$B komi 0.0
$$ --------
$$ | . . . |
$$ | . 1 . |
$$ | . . . |
$$ --------[/go]

Seems always kills all, eye-v-no-eye.

Same question:

$$B komi 0.0
$$ ---------
$$ | . . . . |
$$ | . 1 . . |
$$ | . . . . |
$$ ----------

Click Here To Show Diagram Code

[go]$$B komi 0.0
$$ ---------
$$ | . . . . |
$$ | . 1 . . |
$$ | . . . . |
$$ ----------[/go]

Seems seki.

[sorin]

I can't consider Komi a real rule because it is a tournament addition.

It is true that komi is taking away some of the game's "purity". But luckily, it's a simple and easy addition to the pure rules to make the game fair.

Chess doesn't have such an easy "fix" and it will suffer forever from being unfair.