Life In 19x19

Bill Spight wrote:Button go, anyone?

Bill Spight wrote:Button go, anyone?

With the 4.5 komi the median result on the board was between 6 and 7 for Black, and with the 5.5 komi the median result was between 6 and 7. No fine tuning.

John Fairbairn wrote: 3.75 Chinese komi (said to = Japanese 6.5)

...

However, the sudden leap in White's favour for 3.75 Chinese komi seems potentially anomalous, at least when compared to Japanese/Korean 6.5, and also considering that JK 5.5 vs Chinese 2.75 gives similar results. I can offer no explanation for this, though it does seem to gel with what Chinese pros say about White's advantage. However, in my innumerate naivety I can't help but notice that 2 x 2.75 = 5.5 whereas 2 x 3.75 = 7.5 and not 6.6. In any case, Japanese/Korean 6.5 komi produces the closest B+ vs W+.

John Fairbairn wrote:

With the 4.5 komi the median result on the board was between 6 and 7 for Black, and with the 5.5 komi the median result was between 6 and 7. No fine tuning.

Bill: I'm not sure what you are saying here, but my first impression is that this only shows that pros tend to count out the game when the result falls within a certain band. You need to include resigned games to complete the picture.

pookpooi wrote: "In my experience and the experiments we've run, komi 7.5 is very balanced, we only observe a slightly higher winrate for white (55%)."

Source from DeepMind's Julian Schrittwieser

https://www.reddit.com/r/MachineLearnin ... ittwieser/

luigi wrote:

Bill Spight wrote:Button go, anyone?

I've mentioned this multiple times in this thread already. It would be the perfect solution, but no one seems excited about it.

billyswong wrote:

luigi wrote:

Bill Spight wrote:Button go, anyone?

I've mentioned this multiple times in this thread already. It would be the perfect solution, but no one seems excited about it.

I guess button go being unpopular is because upon introduction of a new object "button", people think of the game as a go-variant, not seeing it a 'proper' ruleset of go anymore, so it's a very perceptual thing.

Bill Spight wrote:I don't think that button go is unpopular; people are just unaware of it.

The equivalent of button go has already been played in international competition. IIUC, go in the Mind Sport Olympiad uses area scoring but if White passes first White gets an extra point.

It is easy to modify AGA scoring to incorporate the equivalent of a button. Under current rules White must pass last, handing over a pass stone. Under the equivalent of button go White must pass last only if Black made the first pass, otherwise Black must pass last. OC, with the pass stones, territory counting is used.

luigi wrote:

Bill Spight wrote:I don't think that button go is unpopular; people are just unaware of it.

The equivalent of button go has already been played in international competition. IIUC, go in the Mind Sport Olympiad uses area scoring but if White passes first White gets an extra point.

It is easy to modify AGA scoring to incorporate the equivalent of a button. Under current rules White must pass last, handing over a pass stone. Under the equivalent of button go White must pass last only if Black made the first pass, otherwise Black must pass last. OC, with the pass stones, territory counting is used.

But, as you explained in some other thread, neither of those is completely equivalent to Button Go. They're just logical implementations of territory scoring. Or am I missing something?

billyswong wrote:So Luigi your first proposal "first passer wins ties" may be more likely to get considered seriously into common use.

komi 5.5               :  B wins ties
komi 7.5               :  W wins ties
button                 :  first passer / dame parity wins ties
somebody had a ko idea :  first passer in final two passes wins ties (may be more tricky)
or                     :  more time left wins ties
or even                :  lower rating wins ties
or politely            :  women or elder wins ties
or just                :  dicethrow wins ties
all to avoid reality   :  no winner in ties :)

Bill Spight wrote:But there are one[-sided] dame, which do not have to be played before the button. For instance, suppose that Black has a one way dame and a territory score of 6. Because she does not have to play the one way dame before the button is taken, she will get an area score of 7.5. After the button is taken, she will have a score of 6.5, and then she takes the one way dame for one more point. Also, there are ko fights that may not be finished until after the button is taken, and they may be exceptions, as well. In addition, it is possible to have positions on the board that are equivalent to a button (I have constructed one), so that who gets the button does not matter.

moha wrote:BTW, even with the button isn't there cases where ko threats decide the winner, after competitive play is over? I'm not sure such behaviour is desirable.

luigi wrote:Let A be a form of area scoring where, if White passes first, White gets an extra point. Komi is 6.5.

Let B be a form of territory scoring with pass stones where White must pass last if Black made the first pass and Black must pass last if White made the first pass. Komi is 6.5.

Let C be button Go (area scoring) with komi 7.

Bill, if B (a modification of AGA rules) is an implementation of double button Go, as you say, how can it also be equivalent to C?

I'm pretty sure A and B are fully equivalent, and I view them as the purest and best forms of territory scoring (much preferable to the convoluted Japanese rules, which I would replace with one of these right away). But you already convinced me that these weren't fully equivalent to C when you said:

Bill Spight wrote:But there are one[-sided] dame, which do not have to be played before the button. For instance, suppose that Black has a one way dame and a territory score of 6. Because she does not have to play the one way dame before the button is taken, she will get an area score of 7.5. After the button is taken, she will have a score of 6.5, and then she takes the one way dame for one more point. Also, there are ko fights that may not be finished until after the button is taken, and they may be exceptions, as well. In addition, it is possible to have positions on the board that are equivalent to a button (I have constructed one), so that who gets the button does not matter.

I think this argument applies to Japanese rules as well as A and B. Under any of those rulesets, if Black passes before playing the one-sided dame, White will just end the game by passing in return. As a result, Black wins by 6 on the board and loses by 0.5 after applying 6.5 komi. Compare this to C, where Black wins by 0.5 by taking the button first and then playing the one-sided dame, as you pointed out.

Bill Spight wrote:Yes, if taking the button counts as a pass for ending play, then there could be problems. That is why I do not advocate doing so. In fact, I have objected to ending play with two consecutive passes for over 20 years. Yasunaga, many years ago, proposed a three pass rule, and Ing has a four pass rule. But I think that the Mind Sports rules end play with two consecutive passes, and count "taking the button" as a pass. I am afraid that I am swimming against the tide.