Beware of analysis deepness

[puzzle_t0rico]

Hi there
In the position below, it is a 7pt match white leads 1-0, green owns the cube and green moves 6-1


I only though about 2 possibilities: 10/4*/3 and 10/4* 1/off
Any other move is just a blunder and 2 free points for white.

When I asked GnuBG to analyse the position, I did it on 0-ply and on 3-ply and the result were REALLY funny
When on 0-ply, hitting and passing was the move to do and the other is a blunder (19'3% of equity loss)


Though, when the analysis is 3-ply deep the results are just the opposite, we must hit and bearoff (17'2% of equity loss)


Fortunately I made the second one and I won but I wonder if it is really the good move. It should be given the equity gain (19'3+17'2=36'5%) but why did he think the blunder was the best?
_________________
If the brain were simple enough to be understood, we would be too stupid to understand it.

[LuvChild]

I believe the answer is in your own statement...

When running the analysis on 0-ply GNU doesn't look past your move and your opponent's next roll. Essentially, they're blind to the chance of you hitting back if white were to hit on your 4-point, or perhaps hitting white's crossing piece along the way- they only see you leaving a blot with a potential to add pips to your count (where you actually lead). In this respect, getting that piece to safety increases your odds of winning in GNU's eyes.

When running the analysis on 3-ply GNU now sees this alternate potential. There existis chances to hit additional white blots if you are sent back; and considering White's 6 checkers already borne off (making the actual pip count- the one necessary to bear off including wastage) taking the chance of getting hit to send another white piece back begins to make sense; but only because now GNU is looking at the potential of your next three rolls and the percentages don't yet call for a double from either side; so you'll get to play at least some of this out.

As an aside: If you hit loose (as you say you did in this match) and White rolled a 5-4... should they hit?

[LuvChild]

I apologize- part ofmy statement is incorrect in so much as wghen I first looked at this I thought the cube was in the center... you get to play it the whole way out- and in fact, if white dances, I believe you come close to a re-double here!