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RO dissapeared

Posted By: John O'Hagan
Date: Monday, 3 June 2013, at 4:28 p.m.

In Response To: 42 for White (John O'Hagan)

What's the gammon value ATS? It's actually right around the normal 50% since single game swings take the leader from 100% to 67% MWC while a gammon loss ties the score with 50% MWC. So the gammon value is only slightly over 50%. So if the ratio of extra wins/extra gammon losses after 18/16x-12 is slightly over 1/2, then hitting's correct, right? That would be true if there was no threat of losing a bg. But hitting here leaves 6 blots around the board - a very bgish thing to do. Not a smart thing to do ATS when the 2-cube bg value is over 200% (~67/33). Notice that 23 of Black's 27 entering numbers hit somewhere so the dreaded hit/dance sequence occurs nearly 1/6 of the time.

So the standard for the hitting play to be correct is that it must increase your winning chances by half your extra gammon-losing chances and 200% of your extra backgammon-losing chances.

The RO dissapeared but it showed that the extra wins were not quite enough to make up for the extra g & bg losses. The RO numbers were very similar to the ++ eval which is shown below. Quietly making your own 5-point is slightly better ATS.

 is Player 2 score: 7 pip: 110 13 point match pip: 134 score: 11 is Player 1
XGID=---BB-CABAA---cbabBc-bb-A-:1:1:1:42:11:7:0:13:10
to play 42

1.XG Roller++9/5 7/5eq: -0.524
 Player:Opponent: 29.17% (G:3.30% B:0.06%)70.83% (G:9.95% B:0.19%)
2.XG Roller++18/16* 16/12eq: -0.529 (-0.005)
 Player:Opponent: 43.45% (G:13.61% B:0.66%)56.55% (G:26.36% B:4.29%)

eXtreme Gammon Version: 2.00, MET: Kazaross XG2

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