From: Jim Segrave <address@hidden>
Reply-To: address@hidden
To: Holger <address@hidden>
CC: olivier croisille <address@hidden>, address@hidden
Subject: Re: [Bug-gnubg] Wrong cube errors categories in analysis
statistics panel
Date: Wed, 1 Oct 2003 02:09:16 +0200
Warning - from someone whose theory is less than awe-inspiring"
Imagine MSC as a line, increasing in value left to right:
You lose------------------------------------------------You win gammon
DP CP TG
1 | 2 3 | 4 5 | 6
The numbers represent regions of MWC.
So for each region, the limits and associated errors:
1 = MWC < DP, error:
double: wrong double around DP
no double: no error
take: no error
drop: wrong drop round DP
2 = DP < MWC < .5 * ( DP + CP)
double: no error
no double: missed double around DP
take: no error
drop: wrong drop round DP
3 = .5 * ( DP + CP) < MWC < CP
double: no error
no double: missed double around CP
take: no error
drop: wrong drop round CP
4 = CP < MWC < .5 * (CP + TG)
double: no error
no double: missed double around CP
take: wrong take around CP
drop: no error
5 = .5 * (CP + TG) < MWC < TG
double: no error
no double: missed double around TG
take: wrong take around TG
drop: no error
6 = TG < MWC
double: wrong double around TG
no double: no error
take: wrong take around TG
drop: no error
Re the other questions
> Does someone know why getMatchPoints() does this and whether this is
> intended?
I can't reproduce this.
From today's CVS, gdb output reformatted for ease of readability:
Breakpoint 2, TheoryUpdated (pw=0x899c740, ptw=0x899b900) at
gtktheory.c:331
1: aaarPointsMatch = {{{0.42115128, 0.328579843},
{0.589850724, 0.589850724},
{0.759432137, 0.767605424},
{0.947443664, 0.767605424}},
{{0.240567863, 0.232394576},
{0.410149246, 0.410149246},
{0.57884872, 0.671420157},
{0.808395922, 0.671420157}}}
(gdb)
And for player 0 in the Market Window, I see the values exactly as
reported above, converted to percentages. There's no swapping visible.
For those who want to test this, this is from:
GNU Backgammon Position ID: sLnJAEzYvg0ICA
Match ID : cInxAAAACAAA
> To categorize cubes gnubg compares the arithmetic means of DP and
> CP, and CP and TG with the winning probabilities. Could someone
> please explain me why (and confirm that) this is correct?
See above, I think it is correct.
> I'm wondering about the following: The winning probability
> (aarOutput[ 0 ][ OUTPUT_WIN ]) doesn't include any added value for
> gammon or bg chances (aarOutput[ 0 ][ OUTPUT_WINGAMMON ] and
> aarOutput[ 0 ][ OUTPUT_WINBACKGAMMON ]). Those match points (DP, CP,
> TG) have an entity of cubeful equity, don't they? And I think
> equities are calculated as the sum of winning chances, gammon
> chances and bg chances, thus include gammon and bg value. If all
> this was correct so far, then I suppose these 2 values can't be
> compared.
This seems a good point - I think picking the point needs to be done
in terms of MWC, it's not enough to do equity, since in some match
points, gammons are irre;evant.
--
Jim Segrave address@hidden