Backgammon Programming

Programming

BKG 9.8 vs. Villa

From:   Raccoon
Address:   racgammon@yahoo.com
Date:   3 August 2006
Subject:   Backgammon champions and computers in 1979
Forum:   rec.games.backgammon
Google:   1154666209.460074.268390@m79g2000cwm.googlegroups.com

"The first strong computer opponent was BKG 9.8. It was programmed by Hans Berliner in the late 1970s on a PDP-10 as an experiment in evaluating board positions. Early versions of BKG played badly even against poor players, but Berliner noticed that the critical mistakes the program made were always at phase changes. He applied basic principles of fuzzy logic to smooth out the transition between phase changes, and by July 1979, BKG 9.8 was ready to play against then current world champion Luigi Villa. It won the match, 7-1, becoming the first computer program to defeat a world champion in any game, although this was mostly a matter of luck, as the computer happened to get better dice rolls than its opponent in that match." --Wikipedia 7 point match Game 1 Villa : 0 Gammonoid : 0 1) 61: 13/7 8/7 44: 24/20 24/20 13/9 13/9 2) 42: 13/9 6/4 Better is 42: 24/20 6/4 2) 44: 20/16* 20/16 6/2 6/2 Better is 44: 20/16*(2) 9/5(2) 3) 61: 25/24 24/18 Doubles => 2 4) Takes 42: 8/4 6/4 How about 42: 13/7*? 5) 43: 8/4 8/5 52: 16/11 9/7* 6) 41: 25/24 13/9* 54: 25/20* 20/16* 7) 53: 25/20 25/22 21: 7/5* 5/4 8) 33: 25/22 7/4 6/3 6/3 51: 16/11 9/8 9) 32: 13/10 24/22 22: 13/11 11/9 11/9 11/9 10) 62: 22/20 20/14 62: 8/2 13/11* Better is 62: 13/7 9/7 11) 51: 25/20 13/12* 66: 12) 33: 12/9 10/7 9/6 6/3 11: 25/24 24/23 6/5* 6/5 13) 55: 31: 23/20 11/10 14) 43: 25/22 22/18 66: 20/14 14/8 10/4 8/2 15) 53: 18/13 13/10 64: 8/2 8/4 16) 51: 10/5 7/6 32: 9/6 6/4 17) 42: 6/2 7/5 62: 4/2 18) 54: 24/19 19/15 Better is 54" 22/13 18) 31: 4/1* 2/1 19) 55: 66: 20) 53: 25/22 15/10 42: 9/5 9/7 21) 65: 22/16 16/11 62: 7/5 5/0 22) 11: 10/9 9/8 8/7 7/6 21: 2/0 1/0 23) 61: 11/5 3/2 64: 5/0 4/0 24) 21: 4/2 2/1 65: 5/0 5/0 25) 55: 22/17 17/12 12/7 7/2 62: 4/0 2/0 26) 43: 22/18 18/15 32: 4/1 2/0 27) 22: 15/13 13/11 11/9 9/7 21: 2/0 1/0 Wins 2 points Game 2 Villa : 0 Gammonoid : 2 1) 63: 24/18 18/15 Most players today would play 63: 24/18 13/10 1) 63: 24/18 13/10* 2) 52: 25/20 20/18 11: 8/7* 8/7 6/5 6/5 3) 54: 25/21 6/1* Doubles => 2 No double ... 4) Drops Wins 1 point Easy take! Game 3 Villa : 0 Gammonoid : 3 1) 52: 13/8 13/11 41: 13/9 6/5 2) 63: 11/5 8/5 44: 13/9 9/5 8/4 8/4 3) 54: 13/8 8/4 64: 8/2 6/2 4) 21: 6/4 6/5 54: 13/8 13/9 Better is 54: 13/8 9/5 5) 41: 8/4 13/12* 63: 25/22 8/2 Better is 63: bar/16 6) Doubles => 2 Takes 7) 51: 8/3* 4/3 66: 8) 63: 8/2 5/2 66: 9) 64: 24/18 18/14 66: 10) 61: 24/18 18/17 66: 11) 41: 17/13 12/11 66: 12) 22: 14/12 13/11 13/11 11/9 66: 13) 21: 11/9 9/8 66: 14) 32: 8/5 12/10 66: 15) 52: 10/5 6/4 66: 16) 53: 11/6 9/6 66: 17) 66: 6/0 6/0 6/0 6/0 62: 25/19 19/17 18) 52: 5/0 5/3 61: 17/11 11/10 19) 64: 5/0 4/0 31: 10/7 7/6 20) 61: 5/0 3/2 62: 24/18 18/16 Villa's next roll is the super antijoker 43, but that's not the only reason 62: 24/16 is not right! 21) 43: 4/0 4/1* 41: 25/24* 16/12 22) 41: 25/24 63: 9/3 6/3 23) 53: 31: 12/9 2/1* 24) 66: 55: 24/19 19/14 14/9 6/1 25) 66: 21: 9/7 9/8 26) 66: 44: 9/5 8/4 7/3 4/0 27) 66: 53: 5/0 3/0 28) 66: 66: 6/0 6/0 5/0 5/0 29) 62: 25/19 19/17 41: 4/0 1/0 Double/pass already. 30) 21: 17/15 15/14 Doubles => 4 31) Drops Wins 2 points Game 4 Villa : 0 Gammonoid : 5 1) 54: 13/8 13/9 42: 8/4 6/4 2) 52: 9/4 6/4 42: 13/9 13/11 3) 44: 24/20 24/20 20/16* 20/16 21: 25/23 6/5 4) Doubles => 2 Drops Wins 1 point A well-played game! In the next and final game, Gammonoid's moves 5, 18 12 and 19 are particularly stinky. Game 5 Villa : 1 Gammonoid : 5 1) 21: 13/11 6/5 2) 21: 13/11 24/23 61: 11/5 6/5 3) 64: 13/7 11/7 21: 6/4 5/4 4) 61: 13/7 23/22 32: 8/5 5/3* 5) 31: 25/22* 24/23 42: 25/23 13/9 6) 62: 22/16* 16/14 53: 25/20 23/20 7) 51: 23/18 14/13 63: 13/7* 13/10 8) 43: 25/22 22/18* 55: 25/20 20/15 8/3 8/3 9) 63: 18/12* 13/10* 32: 25/22 25/23 10) 41: 13/9 10/9 32: 23/20 24/22 11) 42: 8/4 6/4 61: 20/14 14/13* 12) 62: 25/23 13/7 51: 13/8 3/2* 13) Doubles => 2 Takes 14) 32: 25/22* 6/4 42: 25/23 10/6 15) 21: 4/2* 2/1* 53: 25/20 25/22 16) 42: 22/18 18/16 55: 20/15 15/10 10/5 8/3 17) 31: 7/4 16/15 43: 6/2 5/2 18) 41: 15/11 11/10 42: 5/1 5/3 19) 21: 4/2 2/1 22: 22/20 22/20 22/20 3/1 20) 41: 10/6 7/6 55: 20/15 20/15 15/10 15/10 21) 53: 9/4 9/6 33: 10/7 10/7 7/4 7/4 22) 51: 8/3 8/7 32: 20/17 17/15 23) 53: 7/2 6/3 53: 20/15 20/17 24) 33: 7/4 7/4 3/0 3/0 66: 17/11 15/9 15/9 11/5 25) 51: 6/1 1/0 64: 9/3 9/5 26) 51: 6/1 1/0 64: 6/0 4/0 27) 51: 6/1 1/0 42: 4/0 2/0 28) 62: 6/0 2/0 41: 4/0 1/0 29) 54: 6/2 4/0 41: 4/0 1/0 30) 11: 2/1 1/0 1/0 1/0 62: 6/0 2/0 31) 61: 4/0 4/3 21: 2/0 5/4 32) 31: 4/1 1/0 55: 5/0 4/0 3/0 3/0 Wins 2 points and the match Gammonoid knew that backgammon is a race!

Adam Tansley writes:

Thanks Raccoon. And here's what a modern day bot thinks of all that (gnubg 2-ply analysis): Chequerplay statistics Villa Gammonoid Total moves 91 90 Unforced moves 78 73 Unmarked moves 0 0 Moves marked good 87 75 Moves marked doubtful 2 6 Moves marked bad 1 4 Moves marked very bad 1 5 Error rate (total) -0.617 (-7.332%) -2.433 (-22.671%) Error rate (per move) -7.9 (-0.094%) -33.3 (-0.311%) Chequerplay rating Expert Beginner Luck statistics Villa Gammonoid Rolls marked very lucky 0 3 Rolls marked lucky 2 5 Rolls unmarked 86 81 Rolls marked unlucky 3 1 Rolls marked very unlucky 0 0 Luck rate (total) +0.025 (-8.596%) +4.438 (+54.568%) Luck rate (per move) +0.3 (-0.094%) +49.3 (+0.606%) Luck rating None Good dice, man! Cube statistics Villa Gammonoid Total cube decisions 50 52 Close or actual cube decisions 21 8 Doubles 3 3 Takes 1 2 Passes 2 1 Missed doubles (below CP) 3 (-0.048 (-0.351%)) 0 Missed doubles (above CP) 0 1 (-0.038 (-0.505%)) Wrong doubles (below DP) 0 1 (-0.151 (-1.006%)) Wrong doubles (above TG) 0 0 Wrong takes 0 0 Wrong passes 1 (-0.674 (-4.504%)) 0 Error rate (total) -0.723 (-4.855%) -0.189 (-1.511%) Error rate (per cube decision) -34.4 (-0.231%) -23.6 (-0.189%) Cube decision rating Beginner Casual player Overall statistics Villa Gammonoid Error rate (total) -1.340 (-12.187%) -2.622 (-24.182%) Error rate (per decision) -13.5 (-0.123%) -32.4 (-0.299%) Equiv. Snowie error rate -7.4 -14.5 Overall rating Intermediate Beginner Actual result -50.00% +50.00% Luck adjusted result +13.16% -13.16% Luck based FIBS rating diff. +177.04 Error based abs. FIBS rating 1924.4 1616.6 Chequerplay errors rating loss 98.5 414.8 Cube errors rating loss 27.1 18.6 Worth noting that although Gammonoid got very lucky, and Villa had by far the better checker play, Gammonoid actually did better with the cube, according to gnubg. tansley

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