Re: R?f. : Re: [Bug-gnubg] G/BG rates [minor ?]

[Jim Segrave]

On Mon 08 Sep 2003 (14:33 +0000), Joern Thyssen wrote:
> On Mon, Sep 08, 2003 at 02:24:04PM +0200, address@hidden wrote
> > 
> > >
> > >Note as well as Win includes W(g) and W(bg), W(g) includes W(bg), so I'd
> > >expect:
> > >
> > >gammon rate (static) = (13.86-0.41)/48.46 = 27.75%
> > >gammon rate (1-ply)  = (14.01-0.50)/50.32 = 26.85%
> > >gammon rate( 2-ply)  = (13.59-0.44)/48.58 = 27.07%
> > >
> > >I guess the small differences to the ones calculaetd by the market
> > >window is due to rounding errors.
> > 
> > You're right, but I find this a bit confusing.
> > 
> > In the beginning I was asking myself why in the hell the Win/Lose
> > percentages are defined like that (W includes W(g) and W(bg), W(g)
> > includes W(bg), same for L, L(g), L(bg)). Wouldn't be easyier to
> > have W(so), W(go), W(bo) (respectively single only, gammon only
> > and backgammon only) ?
> 
> I don't know.
> 
> The internal representation is W, W(g), and W(bg), and I guess it was
> easiest to use the same externally. Also note that most other bg
> programs use the same representation externally.

I think that's a simple user-friendlieness choice.
The fact that the equity can be determined simply by adding the terms
is one aspect, the other is that it's easier to see that:

.743  .412 .027  

in the current notation is a very strong position. Displaying it as
W(so), W(go), W(bo): 

.331  .385 .027  

makes it harder to see the important fact that you are probably going
to win. On the other hand, the separate probablities make it much
clearer that you are more likely to win a gammon than a single game

-- 
Jim Segrave           address@hidden