FIBS Board backgammon forum

Here is a another hard one. Is it playBunny's time to redouble to 4? And correct answer?

GNU Backgammon  Position ID: f7cBAEDddhMBAA
                 Match ID   : AQEgAWAAAAAA
+12-11-10--9--8--7-------6--5--4--3--2--1-+     O: playBunny (Cube: 2)
|    O        O    |   | O  O  O  O  O  O |     6 points
|                  |   | O  O  O  O  O    |     On roll
|                  |   |    O        O    |     
|                  |   |                  |     
|                  |   |                  |   
^|                  |BAR|                  |     9 point match
|                  |   |                7 |   
|                  |   |                X |     
|                  |   |             X  X |     
|                  |   |       X  X  X  X |     
|                  | X |       X  X  X  X |     0 points
+13-14-15-16-17-18------19-20-21-22-23-24-+     X: You

Pips:
playBunny 67
You 52

(answer in txt-file)

another good one, blitzxz .. i added another answer - Too good to cube, no cube as your last two answers seemed to imply the cube was offered (i added the "if offered" phrase, too) .. only two readers had voted when i did .. so, it shouldn't effect the vote count

keep them coming, blitzxz

hmmm :unsure: when i analyzed the position with GNUbg, i got a different result than blitzxz did in his attached answer file .. mine is included below and i've copied his into mine for comparison

this is not the first time i've encountered different results than others both using GNUbg .. i've also included the SGF file for the position for your convenience .. also, when i set it up with the Position and Match ID's it was WHITE's turn to roll .. so, i advanced it ahead by rolling into the closed board to make it RED's decision
anyone have any ideas about what is going on here? :help:

Neutrality helps the oppressor, never the victim.
Silence encourages the tormentor, never the tormented.
--Elie Wiesel, writer, Nobel laureate (b.1928)

Roll-out changes the result. Roll-out being better then 2-ply. I'm not sure what you mean with too good, no cube?? Do you mean you take and not redouble to 8 on your next turn?? Not using the free redouble won't just ever pay off, even though it might be optinal on the next move.

You could erase that "too good, take" since i put it there only to confuse voters... though it's possible in some special scores. :) And also the problem was meant to be correct cube action for both players. Now the possibilities are little bit mixing. "No cube" meaning both "no double" and "too good" and then there is also 3 "too good" alternatives.  :laugh: You could put only no cube. But I like to keep no double and too good apart since mixing them is serious error that will cost to the player sooner or later.

Spoiler

RED has a slim chance of getting a gammon here, if WHITE dances while RED is bearing off .. a gammon with the cube at 2 would yield a win .. thus it may be "Too good to cube" and "no cube" is thrown .. while this is effectively the  same as your answer, "No cube", GNUbg often uses that as the reason not to cube .. so, i thought i'd add it, too

when i was answering the question before looking at your analysis or mine, i was convinced that would be the best answer .. so, i added it for that reason, as well .. "No cube" alone didn't seem sufficient :lol: turns out i missed it anyway  :frusty: good problem

[close]

i am really not sure i know how or when to do a roll-out using GNUbg .. each time i do one, the results are so close to the ones in the original analysis i seldom bother to do them unless i change an analysis setting, like changing from 2-ply to 3-ply .. i just press the Rollout button in the analysis or hint window .. am i missing something?

Words are the small change of thought.
-Jules Renard, writer (1864-1910)

"i am really not sure i know how or when to do a roll-out using GNUbg .. each time i do one, the results are so close to the ones in the original analysis i seldom bother to do them unless i change an analysis setting, like changing from 2-ply to 3-ply"

Well, roll-outs are the best you can get from the computer. They sometimes change gnu's double decision or backgame checker play. They almost never change normal checker play but might change how big was the error in second or third alternative. There is some guides to use roll-outs in gnu's homepage. I use them when i disagree with gnu's analyzes.

Here's an alternate view, for those who want to see it from the cubist's position. ;)

http://www.gellie.plus.com/DG_Extras/MakeBoard/ShowBoard.htm?mid=UQkgAQAAMAAA&pid=f7cBAEDddhMBAA&player=playBunny&opp=blitzxz&type=cube

(That url's a bit of a mouthful! :laugh:)

There are four little buttons on the right side of the board (where it shows the match length). These can be used to adjust the size and board style (but unfortunately not the home-table side yet).