Re: [Bug-gnubg] Inconsistent match analysis numbers

[Joern Thyssen]

On Mon, Jul 01, 2002 at 03:25:08PM +0100, Ian Shaw wrote
> I find the signs of the error rates and luck rates (and the new ratings)
> confusing.
> 
> I would expect all -ve numbers to indicate a reduced chance of winning the
> match, and all +ve numbers to indicate an increased chance of winning.
> 
> This is the case for the luck rates. Bad luck is a -ve number and good luck
> is +ve.
> 
> Error rates are reported with errors as +ve numbers in the match analysis
> window. This is in contrast to the errors in the annotation window, where
> they are shown as -ve relative to the best move. (The exception is an
> incorrect take which correctly shows up as +ve for the doubler.)

Point taken. This should be fixed in the next build.

> Similarly, the player who is evaluated to be the favourite is shown as
> having a -ve rating w.r.t. to the opponent. This seems counter-intuitive.
> Similarly, the rating w.r.t. "perfect play" is a +ve number. This doesn't
> seem right either.

Ahem, a slight sign error in the rating formula.

> I am also unsure what the "perfect opponent" referred to is. Three possible
> scenarios come to mind.
> 
> 1) The current analysis settings are assumed to be perfect.
> 2) An arbitrary GnuBg setting (e.g. 2-ply) is assumed to be perfect, and
> GnuBg knows the relative strength of it's current setting. I notice that
> currently gnu (2 ply?) is rated c. 2000 and gnu_zp is c. 1900 on FIBS.
> 3) There is a theoretical maximum rating (e.g. 2300) and GnuBg knows its own
> FIBS ranking for the current analysis setting.

I've had a tremendous amount of feedback on the rating stuff. This is
why I've changed it now. I've left the relative rating as it were, but
replaced the "perfect opponent"-rating with a guestimated absolute
rating.

See my post on r.g.b :-)

> Finally, the link <http://www.freeshell.org/~jth/html-images.zip> posted to
> r.g.bg does not work and I can't get a decent export to html now. Can this
> be sorted?

I'm sorry, freeshell.org have changed some setup. The correct URL is
now:

<http://jth.freeshell.org/html-images.zip>

Jørn

-- 
Joern Thyssen, PhD
Vendsysselgade 3, 3., DK-9000 Aalborg, Denmark
+45 9813 2791 (private) / +45 2077 2689 (mobile) / +45 9633 7036 (work)