Life In 19x19

Bill already gave a good review, but let me add my thoughts. I will try to not be too redundant, except where warranted

I think your first slightly wrong move was . Taking the corner is purely territorial and not really bad, but at this stage of the game, efficiency of stones is more important ...

The position at is interesting. You seem to be trying to decide between two reasonable directions of attack. Let me suggest two other alternatives.

How about the center block at K11? This interferes with B development by stopping him from running directly into the center. The idea is to make him ...

I can think of one fairly simple way to gauge the strength of a computer program, relative to a human, expressed in meaningful units. Start playing an even game. The computer evaluates its winning chances after every move as usual. If and when the computer calculates that passing will still result ...

"...Now that I have thickness, what am I supposed to do with it?..."
What could possibly be better use of your thickness than the attack at c7? If colors were reversed, I am quite sure you would be desperate to extend to c8 for safety

The other good alternative is to just leave the thickness ...

The life and death problem on top was nice, but perhaps not classic. B123 was suicide, pretty much forcing W to take the killing liberty B could play F18 instead to live.

You were not losing all the way, but you did get beaten in the fighting a few times, so it is a bit hard to give general advice. In positions where you are locally strong, try harder to find severe moves, to make full use of the strength of your stones. But in positions where you are weak, be more ...

Often Wikipedia is a good source, but seems here it is not.

As Newcomb's problem was explained to me long ago, the predictor has a very high historical accuracy rate (think > 95% but not perfect) at guessing whether someone will take both boxes or only the opaque box. If the predictor thinks you ...

If you allow for minor joseki variation in the bottom three lines of your diagram, Chinese pros have faced this position and played your R11 five times (all in 2017). Twice they played, for Black, from above and twice from below, and once ignored the move. One good rule for choosing an invasion ...

At move 23, you say you do not like the A-B exchange. But would that really be bad? W would end up with 6 stones along the right side of the board, surrounding a total of only around 20 points. That seems hardly worth preventing. Most important, you would end up with sente, which is quite important ...

Here are the graphs for the two positions Bill provided as Go diagrams earlier. The node counts and branch move values are for the gote assumption, with probability 50% for every branch.

o 5.25 o 2.75? really 3
/ \ / \
/ \ -2.75 / \ gote -1.25,
/ \ / \ really sente ...

Start = 4
/ \
sente / \ reverse-sente
/ \ value = -4
/ \
4 0


I don't like this diagram. It relies too much on words and numbers to be understood, and makes it look like a sente is a gote. There is no branch indicating a White reply.

Yes, on reflection I do not like it either. As you ...

This diagram is a good way of looking at my previous simple sente / reverse-sente situation. (I tweaked some of the values from my original post to avoid fractions.)

Start
/ \
/ \
/ \
/ \
A 0
/ \
/ \
/ \
/ \
100 4

From the starting position, W to play (first branch to the right ...

Bill, I was sure you were going to say that the sente move is worth zero. Since the value of the initial position is 2, and the value of the final position (after B sente and W forced response) is still 2, then the value gained by the transaction was 0. Of course B did not have to expend an extra ...

Here is the simplest sente or reverse-sente situation I can think of. Let's see if we can agree on how this is evaluated. No mathlish involved (I hope).

W to play (reverse-sente) can create a final position worth 0 points. It is then B turn to play, somewhere else on the board.
B to play (sente ...

The way I see it - if Black plays there, he has two points, and if not, it's fifty-fifty whether Black gets a point or not. So that would make it a 1.5 point gote. One could also imagine a situation where nothing else is on the board, in which case it would be a 1 point sente (from White's ...