Working through the kyus! (Easier said than done)

Bill Spight · Post by **Bill Spight** » Sun Apr 06, 2014 7:22 am

moyoaji wrote:@Bill - As for your question that I forgot to answer, at R5 seems like the shape point for black's group. It shows up in many joseki. However, I suppose directly defending the cut leaves less aji on the left in this situation. Thanks to your comment I'm now less sure about that move. Maybe it wasn't a terrible mistake after all... (It was probably a mistake )

I am reasonably certain that R-05 would have been a mistake. Yes, it makes a shape that shows up in joseki, but one in which Black responds at R-04 to White R-05. Since Black has already played R-04, why bother to play R-05?

Yes, it threatens to push and cut, but see the SGF file below about that.

Also consider the proverb that my opponent's move is my move. Would Black play at R-05 now? Of course not. It makes bad shape. An immediate cut would be better. Even better, I think, would be the peep at R-08.

I also say this in the SGF file, but it is an important point. Do a tewari on the top right corner. Who came out better in that exchange?

moyoaji · Post by **moyoaji** » Sun Apr 06, 2014 11:37 pm

@Bonobo - Thanks, Tom. Your encouragement on these forums is a great benefit to many of us. I'm glad you appreciate my meanderings here. (Why do you have to be so good, and you make me look so bad...? )

@Bill - Thank you for your comments on my game. That situation in the bottom right was more interesting than I realized. I will try to remember to play a large knight move approach against the iron pillar in the future. Your tewari analysis also clearly shows that O3 would be an overplay in typical joseki.

However, I'm sorry to say that I'm not strong enough to fully understand what happened in the upper right. (No surprise there. ) I looked through the SGF several times and couldn't find a way to do tewari that made sense. I understand that I got a lot of free forcing moves against the corner that forced black to make many small moves in exchange for my wall on the outside, but in the end I count about a 25 point corner for black that is open to the top. I'd hardly see that as a loss for black.

Apparently I need to reassess my view of walls; I've always overvalued territory. So, I will be going back to "Lessons in the Fundamentals of Go" and laying out the joseki failure from page 58 on my go board and telling myself "White's thickness is superior" until it sinks in. (Do you mention that book in every post?) Just like how I learned ladders by reading them out over and over again, hopefully I can learn to appreciate thickness.

I did look up joseki variations on DailyJoseki, finding that I apparently played an uncommon variation by extending to Q14. More common is a move that I forgot from the joseki chapter of "Lessons" - the attachment at N16 following the cut. (You forgot a single thing from "Lessons," eh? Guess you need to study that book harder. ) That variation looks like it would turn out well for me, especially considering how black would be loathe to play R13 to kill my stone off when he has R10 so that stone would not die immediately, giving it more aji. All that said, if my result in the upper right is actually good for white then I shouldn't want to change it.

Bill Spight · Post by **Bill Spight** » Mon Apr 07, 2014 10:17 am

Tewari on the upper right corner.

Click Here To Show Diagram Code: [go]$$B After move 35 $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . X . | $$ | . . . . . . . . . . . . . X O O O X . | $$ | . . . O . . . . . . . . X . O X . O . | $$ | . . . , . . . . . , . X X X O X X X . | $$ | . . . . . . . . . . . . O X X O O X . | $$ | . . . . . . . . . . . . O . . O . X . | $$ | . . . . . . . . . . . . . O . . . . . | $$ | . . . . . . . . . . . . . . . O . X . | $$ | . . . . . . . . . . . . . . . . O O . | $$ | . . . , . . . . . , . . . . . , X . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . X . . . | $$ | . . . O . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

Pairing stones in the corner:

Click Here To Show Diagram Code: [go]$$B Paired stones $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . B . | $$ | . . . . . . . . . . . . . B W W W B . | $$ | . . . O . . . . . . . . X . W B . W . | $$ | . . . , . . . . . , . X X B W X X B . | $$ | . . . . . . . . . . . . O X X O O X . | $$ | . . . . . . . . . . . . O . . O . X . | $$ | . . . . . . . . . . . . . O . . . . . | $$ | . . . . . . . . . . . . . . . O . X . | $$ | . . . . . . . . . . . . . . . . O O . | $$ | . . . , . . . . . , . . . . . , X . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . X . . . | $$ | . . . O . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

Removing paired stones:

Click Here To Show Diagram Code: [go]$$B Paired stones removed $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . O . . . . . . . . X . . . . . . | $$ | . . . , . . . . . , . X X . . X X . . | $$ | . . . . . . . . . . . . O X X O O X . | $$ | . . . . . . . . . . . . O . . O . X . | $$ | . . . . . . . . . . . . . O . . . . . | $$ | . . . . . . . . . . . . . . . O . X . | $$ | . . . . . . . . . . . . . . . . O O . | $$ | . . . , . . . . . , . . . . . , X . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . X . . . | $$ | . . . O . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

Removing the paired stones simply clarifies the situation, like removing paired stones from territory does. The top right corner is pretty much territory, anyway.

Marking inefficiencies:

Click Here To Show Diagram Code: [go]$$Bc Inefficiencies marked $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . O . . . . . . . . B . . . . . . | $$ | . . . , . . . . . , . X X . . X X . . | $$ | . . . . . . . . . . . . O X X O W B . | $$ | . . . . . . . . . . . . O . . O . X . | $$ | . . . . . . . . . . . . . O . . . . . | $$ | . . . . . . . . . . . . . . . O . B . | $$ | . . . . . . . . . . . . . . . . W W . | $$ | . . . , . . . . . , . . . . . , B . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . X . . . | $$ | . . . O . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

The

-

exchange on the 15th rank makes bad shape for White, but is relatively minor. OTOH, Black's empty triangle and extra stone at N-17 is a major inefficiency. As against that, Black has a large corner, bordered on the 4th and 5th lines instead of the 3d and 4th lines. But Black's stones on the S file are inefficient. Also, Black has a broken shape on the right side.

Quick and dirty evaluation:

White's left side is worth about as much as Black's top right corner. Black has made one more move than White, for which we count the stone in the bottom right corner. That leaves the White thickness versus the Black orphan at R-10. By a conservative estimate White has gained more than half a stone.

Edit: This kind of analysis can easily be done during a game.

Bill Spight · Post by **Bill Spight** » Mon Apr 07, 2014 10:57 am

moyoaji wrote:I did look up joseki variations on DailyJoseki,

They have a joseki for the situation with a Black stone at R-10? Given that stone, I would not start with the kake, which invites the push and cut in a region where I am two moves behind. Maybe the shoulder blow at Q-11, to create some strength on the side, or the elephant jump at N-15, as a light play. The kosumi at O-16 is a thought, but then I do not like P-15.

finding that I apparently played an uncommon variation by extending to Q14.

You're a braver man than I am, Gunga Din. I would not leave myself with two weak, separated groups inside my opponent's sphere of influence, where he outnumbers me. Besides, the Black extension to O-15 has a good relation to the pincer stone. I hate to give my opponent good shape.

moyoaji · Post by **moyoaji** » Wed Apr 09, 2014 3:16 pm

Thank you again for your comments, Bill. I am continuing to try to understand outside thickness' value. I'm planning to look at "Attack and Defense" some more today. (Glad you're back to the books. Do you know he actually put the position from "Lessons" on his board? He actually has been looking at it regularly as if that is some form of studying thickness... )

I also need to study "Attack and Defense" because I failed epically in a game yesterday at the West Michigan Go Club. (Oh boy! Another loss! )

This game was embarrassing. My opponent mentioned that he was going to resign after losing his four stones, but that he just wanted to see what would happen. I was clearly ahead and shouldn't have lost. I also neglected to count, a habit that I need to get back into if I want to reach the dan level. (I just want to say that I second his comments on - his gameplay was horrifically bad. )

To say that my attacking backfired in the center is an understatement. I helped black by attacking his groups. So I'm going to take a break from "The Chinese Opening" again to look at "Attack and Defense." (How many people can say that they actively helped their opponent by attacking their opponent's groups? )

Any comments are appreciated.

Bill Spight · Post by **Bill Spight** » Wed Apr 09, 2014 6:50 pm

You were not clearly ahead. Do tewari on the lower left corner.

moyoaji · Post by **moyoaji** » Wed Apr 09, 2014 7:32 pm

Bill Spight wrote:You were not clearly ahead. Do tewari on the lower left corner.

(Bill, I'm afraid you think too highly of moyo. Unlike some players, he can't analyze positions that aren't straight out of a textbook that 20 kyus can read.)

I'm guessing you are referring to the board at :b51:

?

I count 20 points of solid profit in the left corner for white, with access to the left - both because I can undercut his 4th line stone and because the ladder works for me, so I can cut off the knight's move that connects black's lone stone he played. I played only 11 stones to black's 12, got sente, and it started with me approaching black's corner, not with it being my corner to start.

I don't feel like any of my stones are misplaced. That being said, none of black's are either. I don't see any other way I could have played to get a result better than this and I already showed how I thought black should have played. (See what I mean? Clearly the analysis of a 9 dan pro... )

Black is only thick on the bottom. His stones on the left are thin and able to be cut off from the stones on the bottom as I did later. (Yeah, but that snake of stones does nothing for you. A 9 dan pro would never play that way.)

I fail to see how that result was not good for white. Is it that it could have been better somehow?

Or are you referring to the whole board position? Are you saying that even with my superior result I was not ahead after my blunder of the net-able stone? (True, a 9 dan pro wouldn't have pulled out the stone on the right like you did to make black even better off on that half of the board...)

Bill Spight · Post by **Bill Spight** » Wed Apr 09, 2014 8:34 pm

Click Here To Show Diagram Code: [go]$$B Tewari on bottom left corner after $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . O . . . | $$ | . . . X . . . . . , . . O O . , . . . | $$ | . . . . . . . . . . . . . X X . X . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . X . O . . . | $$ | . . . . . . . . . . . . . . . O . . . | $$ | . . . , . . . . . , . . . . X , . . . | $$ | . . . . . . . . . . . . . . X O O . . | $$ | . . . . . . . . . . . . . X O X . O . | $$ | . . . . . X . . . . . . . . O X . . . | $$ | . . . O O X . . . . . . . X . . . . . | $$ | . . W C C O O X . . . . . . . X . . . | $$ | . W C C O X X . X , . . . O . , X . . | $$ | . . W W O O X . . . . . . . . O X . . | $$ | . . . . . . . . . . . . . . . . O O . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

White has captured four stones in the bottom left corner (marked points). We may pair them with four White stones in that corner. Removing them for clarity, we get this diagram.

Click Here To Show Diagram Code: [go]$$B Paired stones removed $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . O . . . | $$ | . . . X . . . . . , . . O O . , . . . | $$ | . . . . . . . . . . . . . X X . X . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . X . O . . . | $$ | . . . . . . . . . . . . . . . O . . . | $$ | . . . , . . . . . , . . . . X , . . . | $$ | . . . . . . . . . . . . . . X O O . . | $$ | . . . . . . . . . . . . . X O X . O . | $$ | . . . . . X . . . . . . . . O X . . . | $$ | . . . O O X . . . . . . . X . . . . . | $$ | . . . . . W W X . . . . . . . X . . . | $$ | . . . , O X X . X , . . . O . , X . . | $$ | . . . . O O X . . . . . . . . O X . . | $$ | . . . . . . . . . . . . . . . . O O . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

A couple of things to note. First, if Black puts the :wc:

stones in atari, it is gote. (If it were sente, then White would have a poorly placed stone on D-06.) Second, if Black captures the stones, it would not be sente in the actual game position, although it would here. So White is slightly better off in the actual game.

Edit: The yose situation is also better for Black. So White is more than slightly better off.

As you point out, White has done well in the corner. It is as though White has been forced to crawl on the fifth line. And Black's position is still not solid. However, any thickness Black gets on the left will work with his thickness on the right.

Black gained by shutting White in on the right side. The question is whether White has caught up, or even pulled ahead. My sense is that the game is close. Maybe White has the edge, but I do not think that either player is clearly ahead.

Bill Spight · Post by **Bill Spight** » Wed Apr 09, 2014 8:45 pm

BTW:

Click Here To Show Diagram Code: [go]$$Wcm62 $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . X . . . . . . X . . . . . O . . . | $$ | . O . X . X . . . , . . O O . , . . . | $$ | . . . . . . . . . . . . . X X . X . . | $$ | . . O . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . X . O . . . | $$ | . . O . . . . . . . . . . X O O . . . | $$ | . . . , . . . . . , . . . 2 X , . . . | $$ | . . . . . . . . . . . . . 1 X O O . . | $$ | . . . X . . . . . . . 8 5 B O X . O . | $$ | . . . . . X . . . . . . 4 3 O X . . . | $$ | . . . O O X O . . . . . . X 6 . . . . | $$ | . . O . . O O X . . . . . . . X . . . | $$ | . O . , O X X . X , . X . O . , X . . | $$ | . . O O O O X . . . . . . . . O X . . | $$ | . . . . . . . . . . . . . . . . O O . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

at

Splatted · Post by **Splatted** » Wed Apr 09, 2014 9:02 pm

@Bill:I'm probably making a fool of my self, but... this seems like a false tewari to me. The difference between your diagram and the actual position is far greater than just the atari of the two stones. In the actual game white's position is about as solid as it's possible to be to the extent that he can completely ignore absolutely any threat black makes against it. Black has no forcing moves, no ko threats, no nothing and much less leeway to leave weaknesses in the area as a result. Those stones are definitely not ideally placed and it would be woefully inefficient to simply play that way without capturing black, but to say that they are equivalent to the black stones which are doing literally nothing* seems to me to be patently false.

I know you're much stronger than me but that's how I see it... :blackeye:

*Actually they cost black a point each.

Bill Spight · Post by **Bill Spight** » Wed Apr 09, 2014 9:43 pm

Splatted wrote:@Bill:I'm probably making a fool of my self, but... this seems like a false tewari to me. The difference between your diagram and the actual position is far greater than just the atari of the two stones. In the actual game white's position is about as solid as it's possible to be to the extent that he can completely ignore absolutely any threat black makes against it. Black has no forcing moves, no ko threats, no nothing and much less leeway to leave weaknesses in the area as a result. Those stones are definitely not ideally placed and it would be woefully inefficient to simply play that way without capturing black, but to say that they are equivalent to the black stones which are doing literally nothing* seems to me to be patently false.

I know you're much stronger than me but that's how I see it...

*Actually they cost black a point each.

Sorry I was not clear. I also did not take the yose on the second line properly into account. (See edit.) That was worth a couple of points.

But I also did not claim that the stones were equivalent. Let me try to be more clear. If they were equivalent, then White would have an inefficient stone at D-06, making bad shape. Then White would have made a small gain in the corner. Instead, White made a substantial gain in the corner. My guess is around 10 pts.

Splatted · Post by **Splatted** » Thu Apr 10, 2014 11:43 am

Bill Spight wrote:
Sorry I was not clear. I also did not take the yose on the second line properly into account. (See edit.) That was worth a couple of points.

But I also did not claim that the stones were equivalent. Let me try to be more clear. If they were equivalent, then White would have an inefficient stone at D-06, making bad shape. Then White would have made a small gain in the corner. Instead, White made a substantial gain in the corner. My guess is around 10 pts.

I think I understand now. You weren't taking off valuable white stones and then saying "look, white's group isn't as good as it appears", you were turning white's group in to a wall so we could more easily see the direction it influences and compare that to black's wall. So in your diagram we see more clearly that white has been successful locally, gaining influence over a large amount of territory, but that black's position is more strategically useful. I'm still not sure this is strictly proper tewari, but at the very least I can see that it's a useful way of analyzing a position.

Bill Spight · Post by **Bill Spight** » Thu Apr 10, 2014 1:17 pm

Splatted wrote:
Bill Spight wrote:
Sorry I was not clear. I also did not take the yose on the second line properly into account. (See edit.) That was worth a couple of points.

But I also did not claim that the stones were equivalent. Let me try to be more clear. If they were equivalent, then White would have an inefficient stone at D-06, making bad shape. Then White would have made a small gain in the corner. Instead, White made a substantial gain in the corner. My guess is around 10 pts.

I think I understand now. You weren't taking off valuable white stones and then saying "look, white's group isn't as good as it appears", you were turning white's group in to a wall so we could more easily see the direction it influences and compare that to black's wall. So in your diagram we see more clearly that white has been successful locally, gaining influence over a large amount of territory, but that black's position is more strategically useful. I'm still not sure this is strictly proper tewari, but at the very least I can see that it's a useful way of analyzing a position.

As everyone says, applying tewari requires judgement. Maybe I am carrying the idea a bit far, but when a number of stones are captured, either in the game or in a variation, pairing the captured stones helps me to clarify the situation. In this case doing so revealed the possible bad shape for White at D-06, E-06, and E-05. That was not obvious when you just saw a bunch of stones. If the atari on the F-05 and G-05 stones had been sente, then the bad shape would have been a feature that the tewari had revealed. That's why I made such a big deal about the atari not being sente.

It may seem like going around Robin's barn to reach a similar conclusion to saying, "Black made a mistake and I captured four stones. Yay!" But I think that it enabled a more precise evaluation to compare with the advantage of the Black wall on the right side.

BTW, I started the habit of pairing captured stones when I first learned about tewari as an SDK. I think that it is particularly valuable at that level because the capture of a number of stones is not uncommon, because it is easy to think that the capture is a good thing, or better than it actually is, and because there are often inefficiencies that pairing stones will reveal. In this case Black was certainly right to play on instead of losing heart.

mitsun · Post by **mitsun** » Thu Apr 10, 2014 3:54 pm

I find tewari analysis occasionally useful in limited circumstances. I have to say that I think Bill is going overboard with the concept here. The original full position appears much easier to analyze than the "tewari" position, which was stripped down so much that it lost important functionality.

The times I have seen tewari analysis applied and found it useful were much more limited in scope. I am thinking specifically of board positions which were reached through one sequence of moves, but tewari analysis showed the same positon reached through a different sequence of moves, and in the tewari version one side played an obviously bad move. In this case tewari analysis reveals which side came out better, without having to count territory or estimate influence. Maybe though my understanding of tewari is too limited.

Bill Spight · Post by **Bill Spight** » Fri Apr 11, 2014 1:56 am

moyoaji wrote:I fail to see how that result was not good for white. Is it that it could have been better somehow?

Or are you referring to the whole board position?

Your analysis of the bottom left corner is fine.

The question is how your substantial gain there tallies with Black's huge wall on the right.

----

BTW, I did not mean to hijack your thread. It is not a place for me to expound my ideas. I will be quite happy to remove my latest tewari discussion (notes #173, 176, 178), if you wish.

Life In 19x19

Working through the kyus! (Easier said than done)

Re: To 5 kyu in 5 months! (We'll see about that)

Re: To 5 kyu in 5 months! (We'll see about that)

Re: To 5 kyu in 5 months! (We'll see about that)

Re: To 5 kyu in 5 months! (We'll see about that)

Re: To 5 kyu in 5 months! (We'll see about that)

Re: To 5 kyu in 5 months! (We'll see about that)

Re: To 5 kyu in 5 months! (We'll see about that)

Re: To 5 kyu in 5 months! (We'll see about that)

Re: To 5 kyu in 5 months! (We'll see about that)

Re: To 5 kyu in 5 months! (We'll see about that)

Re: To 5 kyu in 5 months! (We'll see about that)

Re: To 5 kyu in 5 months! (We'll see about that)

Re: To 5 kyu in 5 months! (We'll see about that)

Re: To 5 kyu in 5 months! (We'll see about that)

Re: To 5 kyu in 5 months! (We'll see about that)