Programming

 N-ply algorithm

 From: eXtreme Gammon Address: contact@extremegammon.com Date: 23 January 2011 Subject: N-ply Algorithm Forum: BGonline.org Forums

```The N-ply Algorithm is pretty straight forward:

* for each 21 dice,

+ check if player should double (using N-ply) and move the cube position

* if N=1,

+ Get the cubeless equity from the NN
+ convert to Cubeful using Janowski formula

* else

+ make the move selected
+ do a (N-1)-ply evaluation of the resulting position

* accumulate the result, weighing them (1/36 for double, 2/36 otherwise)

So yes, a 7-ply will check all 21^6=85,766,121 dice possible.
```

### Programming

Adjusting to a weaker opponent  (Brian Sheppard, July 1997)
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BKG 9.8 vs. Villa  (Raccoon+, Aug 2006)
BKG 9.8 vs. Villa  (Andreas Schneider, June 1992)
BKG beats world champion  (Marty Storer, Sept 1991)
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Board encoding for neural network  (Brian Sheppard, Feb 1997)
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Introduction  (Gareth McCaughan, Oct 1994)
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Methods of encoding positions  (Gary Wong, Jan 2001)
N-ply algorithm  (eXtreme Gammon, Jan 2011)
Neural net questions  (Brian Sheppard, Mar 1999)
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What is a "neural net"?  (Gary Wong, Oct 1998)
Writing a backgammon program  (Gary Wong, Jan 1999)

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