I noticed that Martin Fierz released a new version of his Checkerboard program, so I thought I’d set it sparring against my own program, milhouse. The Cake engine it ships with walks all over my program, but it managed this win against Simple Checkers.

[Event ""]
[Date ""]
[Black "Milhouse"]
[White "Simple Checkers"]
[Result "1-0"]
1. 9-14 23-18 2. 14x23 27x18 3. 5-9 32-27 4. 12-16 27-23 5. 16-20 23-19 6. 20x27 31x24 7.
10-14 26-23 8. 7-10 24-20 9. 8-12 28-24 10. 1-5 22-17 11. 9-13 18x9 12. 5x14 25-22 13. 6-9
23-18 14. 14x23 22-18 15. 13x22 21-17 16. 23-26 30x23 17. 3-8 17-14 18. 10x17 19-15 19.
2-7 23-19 20. 17-21 18-14 21. 9x18 15-10 22. 7x14 19-15 23. 22-25 29x22 24. 18x25 15-10
25. 25-30 10-6 26. 14-18 6-1 27. 18-23 1-6 28. 23-27 6-10 29. 27-32 10-14 30. 12-16 14-18
31. 32-28 18-14 32. 28x19 14-10 33. 30-26 10-7 34. 19-15 7-10 35. 15x6 *


Addendum: I did some quick analysis using both Cake and Milhouse this morning, trying to locate the bad moves that each engine made. I haven’t stared at it too deeply, but it appeared that Simple Checkers walked into a poor opening which I suspect that if I looked hard, I could find in one of my checkers references. Cake finds the first 5 moves in its book, but then Simple Checkers plays 5. … 23-19, which is out of book. Still, upon a 31 ply search, Cake scores the position at -126, which is over a full man down, which would be tough to overcome.

White to move, but is already behind. Simple Checkers has walked into a poor opening. Cake and Milhouse both agree that this position is weak, and White is already almost a full man down.

Addendum: As I suspected, the opening is a known weak one for White, and it begins right back at the second move of the game, although the opening is still part of the standard 3 move opening set, so some possibilities remain. The opening is called the Double Cross, and is considered weak for White (in particular, 1. … 23-18 is not considered a proper response.) Jim Loy has a nifty page full of openings with some insightful commentary, and shows a Tinsley/Fortman game where this opening was featured, with an interesting cook played by Tinsley.

Addendum: Jim Loy has some interesting analysis of the Double Cross opening here.