Life In 19x19

Hi,

In a recent game, my opponent did three monkey jumps . How do I defend against them?.

I looked at the SL pages on this topic and a discussion in the Study Group folder, but I'm struggling to come up with a general rule (along the lines of "hane at the head") that I can recall in the heat of a game. Any suggestions?

Cheers
tezza

Hm let's see if I can write this up before I get ninja'ed.

First, there really is no one answer. Désolé!

Click Here To Show Diagram Code

[go]$$B Monkey jump
$$ -----------------
$$ . . . . . c . . .
$$ . . B . . . . . .
$$ . . B W W @ . @ @
$$ . . X X . . @ @ .[/go]

The two black stones and two white stones in contact make the endgame reducing move at the marked spot playable. The other white stones can be in lots of different places, and they effect best play for black and white.

Click Here To Show Diagram Code

[go]$$B Monkey jump
$$ -----------------
$$ . . . . . c . . .
$$ . . 1 2 . . . . .
$$ . . B W W @ . @ @
$$ . . X X . . @ @ .[/go]

This is the simplest way for W to respond - block as soon as B descends. Whether this is the biggest move on the board of course, is impossible to say. You need to think about what moves W has elsewhere, whether the monkey jump is sente or gote, and whether the hane on the first line will be W's privilege.

(That is to say, when W plays a move where a local followup is sente for W and gote for B, we assume that either W will get to make the followup, or B will have to give up a move elsewhere prevent W's sente: so in this case, if W descends we assume that eventually the board will look like this:)

Click Here To Show Diagram Code

[go]$$B Monkey jump
$$ -----------------
$$ . 5 4 6 . c . . .
$$ . 7 1 2 . . . . .
$$ . . B W W @ . @ @
$$ . . X X . . @ @ .[/go]

Now, once B has made the monkey jump, what should you do? Again, it depends, it all depends. But the obvious move:

Click Here To Show Diagram Code

[go]$$B Monkey jump ending in sente
$$ -----------------
$$ . . . . . 1 . . .
$$ . . X . . 2 . . .
$$ . . X O O O . O O
$$ . . X X . . @ O .[/go]

The key thing to understand is that after W plays on top, B can't get any further into W's territory.

Click Here To Show Diagram Code

[go]$$B Monkey jump ending in sente
$$ -----------------
$$ . . . . 4 1 3 . .
$$ . . X . . 2 . . .
$$ . . X O O O . O O
$$ . . X X . . @ O .[/go]

Click Here To Show Diagram Code

[go]$$B Monkey jump ending in sente
$$ -----------------
$$ . . . 6 3 1 4 . .
$$ . . X . . 2 5 . .
$$ . . X O O O . O O
$$ . . X X . . @ O .[/go]

So B will have to be satisfied with something like this:

Click Here To Show Diagram Code

[go]$$B Monkey jump ending in sente
$$ -----------------
$$ . . . 7 3 1 4 . .
$$ . . X 5 6 2 8 . .
$$ . . X O O O . O O
$$ . . X X . . @ O .[/go]

Depending on surroundings, though, might be elsewhere.

Click Here To Show Diagram Code

[go]$$B Monkey jump ending in sente
$$ -----------------
$$ . . . 3 . 1 4 . .
$$ . . X . . 2 . . .
$$ . . X O O O @ O O
$$ . . X X . . . O .[/go]

Here either W or B has a gote follow-up (capturing/saving ) later.

But even though this is standard doesn't mean you should play it by rote. Sometimes the monkey jump doesn't work at all, and in that case you may need to play your first move elsewhere. You may also have to shift if there are black stones inside the territory that W is trying to defend, or if the white stones on the border are having liberty problems.

Buy yourself a copy of Monkey Jump Workshop" by Richard Hunter, published by Slate and Shell. Actually, being able optimally to deal with all the ramifications of monkey jump situations would make you a strong SDK or dan level player. That's one of the wonderful aspects of the game: fairly simple positions can lead to great complications.

If a monkey comes too early, then the best defense is tenuki and get something bigger elsewhere.

tezza wrote:... I'm struggling to come up with a general rule (along the lines of "hane at the head") that I can recall in the heat of a game. ...

There's a good reason for that: there is no general rule.

Click Here To Show Diagram Code

[go]$$B Monkey jump
$$ -----------------
$$ . . . e d 1 a . .
$$ . . X . . b c . .
$$ . . X O O O . O O
$$ . . X X . . O O .[/go]

Here's the "rule" I use: Read out 'a'. If it works, play it. Otherwise read out 'b', play it if it works. Et cetera... The white stones in the area make a big difference as to what works.

Interesting. I put daniel's b before a.

hyperpape wrote:Interesting. I put daniel's b before a.

I've heard that a is better--if it works.

Click Here To Show Diagram Code

[go]$$B Monkey jump
$$ -----------------
$$ . . . 3 . 1 2 . .
$$ . . X . . 4 . . .
$$ . . X O O O . O O
$$ . . X X . . O O .[/go]

Click Here To Show Diagram Code

[go]$$B Monkey jump
$$ -----------------
$$ . . . 3 . 1 4 . .
$$ . . X . . 2 . . .
$$ . . X O O O . O O
$$ . . X X . . O O .[/go]

In this position, they both should work, but seem to be equal.

Click Here To Show Diagram Code

[go]$$B Monkey jump
$$ -----------------
$$ . . . c . B a . .
$$ . . X . . b . . .
$$ . . X O O O . O O
$$ . . X X . . O O .[/go]

there are three way to answer a,b,c
a is the best if it works.
b is the second best if it works.
c is the safest way to stop but will lose more points.

a and b usually have 1/2 point difference.
b and c usually have 1/2 point difference.

which means a and c have 1 full point difference usually.

if it is wide open as below... you will not be able to stop with a or b or c.

Click Here To Show Diagram Code

[go]$$B Monkey jump
$$ -----------------
$$ . . . . . B . . .
$$ . . X . . . . . .
$$ . . X W . . . . .
$$ . . X W . . . . .[/go]

brilliant post Daniel..magicwand...

Great posts! Thanks .

Magicwand wrote:

$$B Monkey jump
$$ -----------------
$$ . . . c . B a . .
$$ . . X . . b . . .
$$ . . X O O O . O O
$$ . . X X . . O O .

Click Here To Show Diagram Code

[go]$$B Monkey jump
$$ -----------------
$$ . . . c . B a . .
$$ . . X . . b . . .
$$ . . X O O O . O O
$$ . . X X . . O O .[/go]

a and b usually have 1/2 point difference.
b and c usually have 1/2 point difference.

Can someone give an example of when a would be better than b?

Magicwand wrote:if it is wide open as below... you will not be able to stop with a or b or c.

$$B Monkey jump
$$ -----------------
$$ . . . . . B . . .
$$ . . X . . . . . .
$$ . . X W . . . . .
$$ . . X W . . . . .

Click Here To Show Diagram Code

[go]$$B Monkey jump
$$ -----------------
$$ . . . . . B . . .
$$ . . X . . . . . .
$$ . . X W . . . . .
$$ . . X W . . . . .[/go]

I've heard, though, that in this situation the monkey jump is a mistake and jumping on the second line is better. Thoughts?

Click Here To Show Diagram Code

[go]$$B Monkey jump
$$ -----------------
$$ . . . . . . . . .
$$ . . X . B . . . .
$$ . . X W . . . . .
$$ . . X W . . . . .[/go]

Jts: It seems to be complicated: http://senseis.xmp.net/?MonkeyJump%2FOrOneSpaceJump.

I would also like to see a case where the first line move is better: I'll be watching any games I look at.

I think this is one example. I'm sure MW can come up with a better one.

Click Here To Show Diagram Code

[go]$$B Monkey jump
$$ -----------------
$$ . . . . . B . . .
$$ . . X . . . . . .
$$ . . X O . O O O O
$$ . . X O O O . . .[/go]

jts wrote:

Magicwand wrote:

$$B Monkey jump
$$ -----------------
$$ . . . c . B a . .
$$ . . X . . b . . .
$$ . . X O O O . O O
$$ . . X X . . O O .

Click Here To Show Diagram Code

[go]$$B Monkey jump
$$ -----------------
$$ . . . c . B a . .
$$ . . X . . b . . .
$$ . . X O O O . O O
$$ . . X X . . O O .[/go]

a and b usually have 1/2 point difference.
b and c usually have 1/2 point difference.

Can someone give an example of when a would be better than b?

This looks like a good example, depending on what the situation is on the right.

Click Here To Show Diagram Code

[go]$$W Monkey jump
$$ -----------------
$$ . . a 2 6 B 3 . .
$$ . . X . . 1 7 . .
$$ . . X O O O . O O
$$ . . X X . O O O .[/go]

If , then and . (Sorry about that. ) If the situation is such that later is sente, it leaves ½ point for Black at "a".

Click Here To Show Diagram Code

[go]$$W Monkey jump
$$ -----------------
$$ . . a 2 6 B 1 . .
$$ . . X 5 . . 3 . .
$$ . . X O O O . O O
$$ . . X X . O O O .[/go]

If , then is sente (we assume). Later is sente, threatening a throw in at 6. There is no point at "a".

Edit: Magicwand is right about Black's reply when White makes the wrong play.

Click Here To Show Diagram Code

[go]$$W Monkey jump
$$ -----------------
$$ . . a 6 2 B 3 . .
$$ . . X 4 5 1 7 . .
$$ . . X O O O . O O
$$ . . X X . O O O .[/go]

Black should simply pull back with . Now Black gets a full point at "a", not a half point.