Re: [Bug-gnubg] Bearoff database

[Philippe Michel]

On Sun, 8 Jan 2017, isambard mews wrote:

> I tried to recreate the bearoff database and noticed some differences 
> which could be due to rounding, but already at position #47 there were 
> some significant differences. My workings for position 47 are given 
> below. Have I made a mistake in the calculation methodology?

Th discrepancy for position #47 is not a rounding error. The difference is 
11/1296 more bearoffs in 2 rolls instead of 3 for gnubg.

Interestingly, the average number of rolls to bear off is 2.21382 for you 
and 2.20528 for gnubg but the race4 software there : 
http://www.bkgm.com/rgb/rgb.cgi?view+788 that works recursively and plays 
perfectly claims that the average is 2.117155, so it looks like gnubg 
misplays a dice in one situation and you do in two.