[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Bug-gnubg] Hint on cube decisions
From: |
Kari Uusitalo |
Subject: |
Re: [Bug-gnubg] Hint on cube decisions |
Date: |
Fri, 16 Jun 2006 18:16:43 +0300 |
Thanks, that helped!
Still I wonder the beaver/redouble things. I tried it with two human
players and the results were somewhat odd as you can see below. I have
but some comments and a quiestion in between.
BR,
Kari
The game output:
(user) hint
Cube analysis
2-ply cubeless equity +0.872
0.773 0.345 0.043 - 0.227 0.059 0.002
Cubeful equities:
1. Double, pass +1.000
2. Double, take +1.589 ( +0.589)
3. No double +0.971 ( -0.029)
Proper cube action: Double, pass
The doubling seems like a very good advice as we are leading so heavily.
(user) double
user doubles.
GNU Backgammon Position ID: YefBADhsm8gRQA
Match ID : cBEAAAAAAAAA
+13-14-15-16-17-18------19-20-21-22-23-24-+ O: gnubg
| X X O | | O O O | 0 points
| X O | | O O | Cube offered at 2
| X O | | O |
| O | | |
| | | |
v| |BAR| |
| | | |
| | | |
| | | O |
| O | | X X X X O |
| O X X | X | X X X X O | 0 points
+12-11-10--9--8--7-------6--5--4--3--2--1-+ X: user
(gnubg) hint
Take decision:
Equity for take: -1.589
Equity for pass: -1.000
Your proper cube action: Pass.
This also seems like a good advice as gnubg player is behind so clearly.
However, he redoubles just for this test.
(gnubg) beaver
gnubg accepts and immediately redoubles to 4.
GNU Backgammon Position ID: YefBADhsm8gRQA
Match ID : QRkAAAAAAAAA
+13-14-15-16-17-18------19-20-21-22-23-24-+ O: gnubg
| X X O | | O O O | 0 points
| X O | | O O |
| X O | | O |
| O | | |
| | | |
v| |BAR| |
| | | |
| | | |
| | | O |
| O | | X X X X O | Cube offered at 4
| O X X | X | X X X X O | 0 points
+12-11-10--9--8--7-------6--5--4--3--2--1-+ X: user
(user) hint
Take decision:
Equity for take: -1.592
Equity for pass: -1.000
Your proper cube action: Pass.
How can the correct action be to "Pass" when the user is leading so much?
2006/6/16, Ian Shaw <address@hidden>:
From: Kari Uusitalo Sent: 16 June 2006 11:38
> I am playing around with the GNU BG and tried to find info
> about what excatly different lines mean in hint ouputs ofr
> cube selection.
>
> For example, I have the cube in a certain game situation and
> the hint returns:
>
> >>>>>>>>
> Cube analysis
> 2-ply cubeless equity -0.039
> 0.479 0.108 0.002 - 0.521 0.105 0.002
> Cubeful equities:
> 1. No double +0.124
> 2. Double, pass +1.000 ( +0.876)
> 3. Double, take -0.433 ( -0.556)
> Proper cube action: No redouble, beaver (38.8%)
> >>>>>>>>
>
> What exactly the different lines mean. I guess, the last line
> is the most important and in this case I should not double.
> What does the "beaver"-text in that particular line mean and
> what does the percentage figure stand for?
When an opponent doubles, some games allow to to Beaver. E.g. If Player
A doubles to 2, Player B can Beaver to 4 - keeping the cube on his side.
Roughly speaking, you should beaver if your opponent has doubled you
when you are the favourite to win, as in the example above. The opponent
is expected to win 52.1% of the games, so gnubg recommends that you
don't double, but if you do, then the opponent should beaver.
The 38.8% figure means that the double would be correct if 38.8% of
opponents were to mistakenly pass the double.
I hope this helps.
-- Ian Shaw