Game 7, move 5 : roadkillbooks 4-2

[diane]

Sorry, no 6-3 here....

rkb, white, to move 4-2

zO4sAAMsz4wBMA:EQGxADAAIAAA

[roadkillbooks]

8/4, 8/6

[NIHILIST]

Spoiler

I think he's stripping his position pretty badly here. In one way, clearing his 8 point doesn't hurt him in the sense of giving us a joker since we'd play 3-3 to make our 4 point. On the other hand he's removing checkers he might soon need to attack us with. The 2 plays I'd consider are 6-4, 6-2 and 6-2, 4-2. I have the feeling that, over the board, I'd make the 2 point and keep a spare on the 6 point.

[close]

Bob

[ah_clem]

Spoiler

I think he's stripping his position pretty badly here. In one way, clearing his 8 point doesn't hurt him in the sense of giving us a joker since we'd play 3-3 to make our 4 point. On the other hand he's removing checkers he might soon need to attack us with. The 2 plays I'd consider are 6-4, 6-2 and 6-2, 4-2. I have the feeling that, over the board, I'd make the 2 point and keep a spare on the 6 point.

I was also scratching my head about this move.  I thought 6/4 6/2 was the obvious choice, but I didn't put the mental energy into it like I do with our moves.  I'll start a rollout, but I won't be ready to post it til morning.

[close]

[dorbel]

Spoiler

Interestingly, Snowie will play 13/9, 6/4. This makes another point inboard and bids to make another blocking point. If we hit, he buys some timing and some joker fly shots from the bar. Not sure I would even have seen it over the board (!) but once you do see it, it looks pretty cool.

[close]

spoiler added - since I havent progressed the game yet  Diane

[diane]

Spoiler

Me too...flabbergasted - and do so resent it when I find myself in agreement with NIHI...again!!        Those are the two moves I thought rkb would like to debate.  Anyhoo, will move it later on tonight.

[close]

[ah_clem]

gnubg rollout

Spoiler

gnubg also likes 13/9 6/4, with the gutsy 13/11 8/4 not too far behind. Interesting.  I would have described 13/11 8/4 as "suicidal".  perhaps some of teh better players around here can explain it.


The solid 6/2 4/2 is not far behind and is ny no means a blunder at .01 equity difference.  Quietly making the 4 point is about the same.  rkb's move comes in 7th as a .025 error.



    1. Rollout          13/9 6/4                     Eq.:  -0.534
       0.233 0.062 0.006 - 0.767 0.384 0.092 CL  -0.534 CF  -0.534
      [0.002 0.003 0.002 - 0.002 0.007 0.006 CL   0.004 CF   0.004]

    2. Rollout          13/11 8/4                    Eq.:  -0.540 ( -0.006)
       0.230 0.050 0.004 - 0.770 0.408 0.118 CL  -0.540 CF  -0.540
      [0.002 0.002 0.001 - 0.002 0.007 0.006 CL   0.004 CF   0.004]

    3. Rollout          6/2 4/2                      Eq.:  -0.544 ( -0.010)
       0.228 0.055 0.003 - 0.772 0.379 0.054 CL  -0.544 CF  -0.544
      [0.002 0.003 0.001 - 0.002 0.007 0.004 CL   0.004 CF   0.004]

    4. Rollout          6/4 6/2                      Eq.:  -0.546 ( -0.012)
       0.227 0.057 0.004 - 0.773 0.384 0.063 CL  -0.546 CF  -0.546
      [0.002 0.003 0.001 - 0.002 0.007 0.005 CL   0.004 CF   0.004]

    5. Rollout          13/7                         Eq.:  -0.548 ( -0.015)
       0.226 0.056 0.006 - 0.774 0.396 0.111 CL  -0.548 CF  -0.548
      [0.002 0.003 0.002 - 0.002 0.007 0.006 CL   0.005 CF   0.005]

    6. Rollout          8/4 6/4                      Eq.:  -0.555 ( -0.021)
       0.223 0.049 0.004 - 0.777 0.385 0.071 CL  -0.555 CF  -0.555
      [0.002 0.003 0.001 - 0.002 0.007 0.005 CL   0.004 CF   0.004]

    7. Rollout          8/6 8/4                      Eq.:  -0.558 ( -0.025)
       0.221 0.054 0.003 - 0.779 0.367 0.063 CL  -0.558 CF  -0.558
      [0.002 0.003 0.001 - 0.002 0.007 0.005 CL   0.004 CF   0.004]

    8. Rollout          8/2                          Eq.:  -0.571 ( -0.037)
       0.214 0.051 0.005 - 0.786 0.411 0.113 CL  -0.571 CF  -0.571
      [0.002 0.003 0.001 - 0.002 0.007 0.006 CL   0.005 CF   0.005]

    9. Rollout          10/4                         Eq.:  -0.571 ( -0.038)
       0.214 0.054 0.002 - 0.786 0.375 0.064 CL  -0.571 CF  -0.571
      [0.002 0.003 0.002 - 0.002 0.007 0.005 CL   0.004 CF   0.004]

   10. Rollout          13/11 6/2                    Eq.:  -0.574 ( -0.040)
       0.213 0.050 0.007 - 0.787 0.454 0.143 CL  -0.574 CF  -0.574
      [0.003 0.003 0.002 - 0.003 0.008 0.007 CL   0.006 CF   0.006]
        Full cubeful rollout with var.redn.
        1296 games, Mersenne Twister dice gen. with seed 841902667 and quasi-random dice
        Play: 0-ply cubeful prune [expert]
        Cube: 0-ply cubeful prune [expert]

[close]

[dorbel]

There is no need to have a spoiler when we are talking about a move that has already been made is there? RKB has played and picked up his dice. Let's roll!
What is the point of the slot plays that the bots like? White is stripped in the outfield and will soon have to break points anyway, often leaving shots in the process. That's not enough in itself to justify slotting, but these are very positive slots, aimed at making valuable blocking points. Not only that but they are often free slots, because Blue won't usually want to hit them! Lay out the "suicidal" 13/11, 8/4 and ask yourself how many of the 26 shots this generates Blue will actually want to hit? It's pretty clear to hit with 6-6, 6-4 and 4-4. 3-3 is possible but by no means clear. The other 21 numbers invite Blue to make a mistake by hitting! It must be worth giving five shots mustn't it? This has come about because Blue can't double, so must make a prime to win and can't benefit from a gammon, so has no interest in sending more checkers back. It's much rarer than people imagine to see an opportunity for a brilliant and visionary play; this is one. Note the environment in which it has occurred (dead cube, gammon free) and make a resolution to look outside the box for your play when you are on the ropes in that kind of game. I wouldn't have considered 13/9, 6/4, let alone 13/11, 8/4, but I should have done!

[ah_clem]

There is no need to have a spoiler when we are talking about a move that has already been made is there?

Probably not.  You can say the same thing about rollouts of our moves after we've picked up the dice.  I've been putting the rollouts behind a spoiler out of habit, and didn't see a reason to change here.  My take is that there's not much reason for spoilers at all - if you don't want to read what others have to say, don't scroll down.

BTW, spoiler buttons only show up if you're logged in.  If someone is lurking, all they see in these threads are blank posts.

The other 21 numbers invite Blue to make a mistake by hitting! It must be worth giving five shots mustn't it?

My understanding is that bot results are based on subsequent optimal play from both sides, so the bot wouldn't take "my opponent might make a mistake here" into account. Of course, when playing humans one might want to make  play that gives them the biggest chance to muff it up, even if it's theoretically inferior according to the bot.  But now we're into the "play the board" vs "play the opponent" portion of the discussion which has been done to death....

The rest of your analysis makes sense.  Especially the part about thinking outside the box when the cube is dead and gammons don't count.  Thanks.

[diane]

There is no need to have a spoiler when we are talking about a move that has already been made is there? RKB has played and picked up his dice. Let's roll!

No - sure if I had moved it on, but I was at work and hadn't seen the move, and hadn't moved it on - once  it is moved on, no problem at all - although I know that rkb wouldnt change his mind like we do, of course