I got asked what to think about an early pincer:
I let ELF answer (Have a look at the different winrates for black):
To pincer or not to pincer:
-
00Noles
- Dies in gote
- Posts: 41
- Joined: Tue May 22, 2018 11:30 pm
- GD Posts: 0
- Has thanked: 19 times
- Been thanked: 1 time
Re: To pincer or not to pincer:
I think its because those strong bots don't value influence very much (as they probably know how to deal with it very well). Hence the high win probabilities for the early 3-3.
-
EdLee
- Honinbo
- Posts: 8859
- Joined: Sat Apr 24, 2010 6:49 pm
- GD Posts: 312
- Location: Santa Barbara, CA
- Has thanked: 349 times
- Been thanked: 2070 times
-
Uberdude
- Judan
- Posts: 6727
- Joined: Thu Nov 24, 2011 11:35 am
- Rank: UK 4 dan
- GD Posts: 0
- KGS: Uberdude 4d
- OGS: Uberdude 7d
- Location: Cambridge, UK
- Has thanked: 436 times
- Been thanked: 3718 times
Re: To pincer or not to pincer:
When I was in BIBA in 2013 On Sojin 7p said he didn't think pincer was good in parallel 4-4s, just back off better. Reason is the take corner joseki is locally good for black (even more obvious now if you compare it to 3-3 invasions now considered even) so pincer should only be played if pincer direction is particularly important. So if lower right is a 3-4 towards right edge then approach there is a good move for white to spend the sente afterwards which makes pincer plausible, and pincer also disrupts mini-Chinese type openings (psychological value too). I suppose Elf thinks that pincer is bad too, but not so much.
-
Uberdude
- Judan
- Posts: 6727
- Joined: Thu Nov 24, 2011 11:35 am
- Rank: UK 4 dan
- GD Posts: 0
- KGS: Uberdude 4d
- OGS: Uberdude 7d
- Location: Cambridge, UK
- Has thanked: 436 times
- Been thanked: 3718 times
Re: To pincer or not to pincer:
Checking AlphaGo Teach (probably stronger than Elf, but sometimes I have doubts) for the Sojin argument:
With parallel 4-4s, pincer is 46.9% for black, back off is 44.9% (and best).
If pincer then 3-3 invade top left is best (46.6%, != 46.9 so we can see these values have a few tenths of a percent variation). Lower left 3-3 is 43.7, i.e. more of a mistake that white's pincer. With the normal human joseki, AGT says black ends with 46.5 at the end (if top right 3-3), more normal human o3 approach is similar at 46.7. So AG agrees that this end result is better for black than if white just backed off initially, and basically the same as after the pincer. Agrees with Sojin/me.
However, both players have made significant mistakes! As discussed on the boards before, white 14 should have not been solid connect but underneath for a 5% better result. So if white does this black loses a lot more than the small gain he got from white's bad pincer. This move wasn't unknown to humans before and has been played a few times, but was a fairly obscure move. My wife remembers being told off by her teachers when she wanted to play here. Also instead of 11 hane AGT says black should have played b6 knight move (2% difference), I suppose this doesn't damage f3 so much. Disagrees with Sojin/me.
How about the lower right being a 3-4 point?
TBC
P.S. I don't think this belongs in Beginners forum!
With parallel 4-4s, pincer is 46.9% for black, back off is 44.9% (and best).
If pincer then 3-3 invade top left is best (46.6%, != 46.9 so we can see these values have a few tenths of a percent variation). Lower left 3-3 is 43.7, i.e. more of a mistake that white's pincer. With the normal human joseki, AGT says black ends with 46.5 at the end (if top right 3-3), more normal human o3 approach is similar at 46.7. So AG agrees that this end result is better for black than if white just backed off initially, and basically the same as after the pincer. Agrees with Sojin/me.
However, both players have made significant mistakes! As discussed on the boards before, white 14 should have not been solid connect but underneath for a 5% better result. So if white does this black loses a lot more than the small gain he got from white's bad pincer. This move wasn't unknown to humans before and has been played a few times, but was a fairly obscure move. My wife remembers being told off by her teachers when she wanted to play here. Also instead of 11 hane AGT says black should have played b6 knight move (2% difference), I suppose this doesn't damage f3 so much. Disagrees with Sojin/me.
How about the lower right being a 3-4 point?
TBC
P.S. I don't think this belongs in Beginners forum!