Snowie

Forum Archive : Snowie

 Error rates

 From: Gregg Cattanach Address: gcattanach@prodigy.net Date: 8 October 2000 Subject: Re: Explanation of Snowie Error Rates: Forum: rec.games.backgammon Google: 8rr0dg\$7qim\$1@newssvr05-en0.news.prodigy.com

```> 1. When snowie says i had a combined checker and cube error of 7.5, what
>    does that actually mean?  I lost .75 of a point due to my
>    incompetance? or .75 of a match?  or something else?
> 2. Snowie will analyze my matches and say something like... "4 cube
>    errors including 1 blunder"... but then when i "explore" my matches,
>    I might find 3 cube decisions highlighted as "blunders"  how can this
>    be?

There are two error rates quoted at the end of each Snowie HTML output
match.

The first is the EMG (Equivalent Money Game) figure.  This figure does NOT
take into effect the match equity lost by your errors, but treats each game
separately as if it were a money game.  The figure is in 'millipoints per
move'.  So in a match with exactly 100 moves (both players), if you gave up
.075 in equity on one move only, you would have an error rate of 0.75
(which would be EXTREMELY good.).  If you gave up a total of .750 equity
over all your errors then you'd get an EMG error rate of 7.5.

The second is the MWC (Match Winning Chances) error rate, which is a
percentage.  If the total amount of match equity you gave up over all your
errors was 20%, then this number is 20.00.

The first number is good to look at how you played in all games equally
(you don't want to make errors at any match score).  The second shows you
the cost in the match of your errors, based on which games and the level of

This is also well explained in the Snowie Help text.

Hope that helps :)
--
Gregg Cattanach
Zox at GamesGrid, Zone
http://gateway.to/backgammon
```

### Snowie

Announcement  (Olivier Egger, Apr 1998)
Checker-play-according-to-score bug  (Peter Schneider+, June 2001)
Error rates  (Gregg Cattanach, Oct 2000)
Hints and questions  (Achim Müller+, Aug 1998)
Luck calculation  (Gregg Cattanach+, Dec 1999)
Questions and answers  (David Montgomery, Dec 1998)
Running in low priority  (lmfback+, Oct 2004)
Snowie 4.0  (SnowieGroup Info, Oct 2002)
Snowie 4.3 update  (Gregg Cattanach, July 2005)
Snowie cube evaluation  (Kit Woolsey, Sept 2007)
Snowie vs GNU  (Stanley E. Richards+, Oct 2005)
Snowie vs. Jellyfish  (Mark Driver, Apr 2001)
Snowie vs. Jellyfish  (Daniel Murphy, Oct 2000)
Snowie vs. Jellyfish  (Gregg Cattanach+, Sept 2000)
Snowie vs. Jellyfish  (Wayne Crookes, Jan 1999)
Snowie vs. Jellyfish  (Kenneth M. Arnold+, May 1998)
Terminology  (Alexander Nitschke, Sept 1998)
Using rollouts  (Michael J. Zehr+, Oct 1998)