Re: [Bug-gnubg] Bug#659494: Resigns more points than necessary when fewer points would still result in opponent win

[Michael Petch]

On 14/02/2012 3:32 PM, Joseph Heled wrote:
> if the bot does not care about points lost, it should resign, no?
> 
In the case I showed yes, the bot would have already resigned. But in my
example I used it as a "edit position" and asked the bot to tell me what
it should do with the play. Although outside a complete match. My
example may not have been the best one. A better example is probably
this one:

    GNU Backgammon  Position ID: CgAA2Lo7AAACAA
                    Match ID   : 8AlgAaAAAAAA
    +24-23-22-21-20-19------18-17-16-15-14-13-+  O: mpetch
OOO |    O  O          |   |                  |  10 points
OOO |                  |   |                  |
OOO |                  |   |                  |
 OO |                  |   |                  |
 OO |                  |   |                  |
    |                  |BAR|                  |v 11 point match (Cube: 1)
    |                  |   |                  |
    |                  |   |                  |
    |          X  X  X |   |                  |
    | X  X     X  X  X |   |                  |  On roll
    | X  X  X  X  X  X | X |                  |  0 points
    +-1--2--3--4--5--6-------7--8--9-10-11-12-+  X: gnubg

    1. Cubeful 2-ply    bar/15 6/1(2)                MWC:   0.000%
       0.0000 0.0000 0.0000 - 1.0000 0.9830 0.0000
        2-ply cubeful prune [world class]
    2. Cubeful 2-ply    bar/20 6/1(3)                MWC:   0.000% (
0.000%)
       0.0000 0.0000 0.0000 - 1.0000 0.9830 0.6944
        2-ply cubeful prune [world class]
    3. Cubeful 2-ply    bar/5                        MWC:   0.000% (
0.000%)
       0.0000 0.0000 0.0000 - 1.0000 0.8981 0.0000
        2-ply cubeful prune [world class]
    4. Cubeful 2-ply    bar/10 6/1                   MWC:   0.000% (
0.000%)
       0.0000 0.0000 0.0000 - 1.0000 0.9830 0.0000
        2-ply cubeful prune [world class]



The Bot had a chance to win before the roll, but not after. In this case
it happens that it plays bar/15 6/1(2). It doesn't save the gammon, and
on next roll the bot will resign. It could have saved the gammon but it
didn't. Apply same argument from my original position to this.

-- 
Michael Petch
CApp::Sysware Consulting Ltd.
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