I added code to detect unstoppable passed pawns and drawn endgames, and code to evaluate material trades. The code that evaluates material trades implements the age old advice, “When ahead trade pieces. When behind trade pawns.” A greater bonus is giving for trading pawns, since in many endgames the side with a material advantage cannot win without promoting a pawn.
This added 39 Elo to the playing strength of MadChess 2.0 Beta.
MadChess 2.0 2193 : 800 (+399,=168,-233), 60.4 % vs. : games ( +, =, -), (%) : Diff, SD, CFS (%) Glass 1.6 : 50 ( 4, 7, 39), 15.0 : -223, 27, 0.0 Sungorus 1.4 : 50 ( 18, 7, 25), 43.0 : -117, 12, 0.0 ZCT 0.3.2450 : 50 ( 13, 12, 25), 38.0 : -15, 14, 14.3 FireFly v2.6.0 : 50 ( 18, 19, 13), 55.0 : -13, 15, 19.0 Jazz v444 : 50 ( 19, 15, 16), 53.0 : +9, 14, 73.6 Beowulf 2.4 : 50 ( 21, 13, 16), 55.0 : +31, 20, 93.9 Wing 2.0 : 50 ( 22, 11, 17), 55.0 : +71, 15, 100.0 Brainless 1.0 : 50 ( 26, 11, 13), 63.0 : +82, 19, 100.0 BikJump v2.01 : 50 ( 22, 10, 18), 54.0 : +93, 13, 100.0 Matheus-2.3 : 50 ( 21, 17, 12), 59.0 : +115, 13, 100.0 Monarch 1.7 : 50 ( 28, 11, 11), 67.0 : +142, 15, 100.0 BigLion 2.23w : 50 ( 32, 12, 6), 76.0 : +170, 13, 100.0 Sharper 0.17 : 50 ( 37, 5, 8), 79.0 : +184, 13, 100.0 Faile 1.4 : 50 ( 36, 12, 2), 84.0 : +213, 12, 100.0 Jabba13032012 : 50 ( 41, 1, 8), 83.0 : +242, 13, 100.0 Roce 0.0390 : 50 ( 41, 5, 4), 87.0 : +311, 13, 100.0
Feature | Category | Date | Rev1 | WAC2 | Elo Rating3 | Improvement |
---|---|---|---|---|---|---|
Unstoppable Pawns Draws, Material Trades |
Evaluation | 2015 Jan 31 | 52 | 270 | 2193 | +39 |
Late Move Pruning | Search | 2015 Jan 10 | 44 | 273 | 2154 | +39 |
History Heuristic Late Move Reductions |
Search | 2015 Jan 04 | 40 | 275 | 2115 | +50 |
Killer Moves | Search | 2015 Jan 03 | 38 | 275 | 2065 | +61 |
Futility Pruning | Search | 2014 Dec 29 | 37 | 256 | 2004 | +54 |
Null Move Quiescence Recaptures |
Search | 2014 Dec 28 | 34 | 242 | 1950 | +46 |
King Safety | Evaluation | 2014 Dec 24 | 32 | 225 | 1904 | +27 |
Piece Mobility | Evaluation | 2014 Dec 16 | 29 | 225 | 1877 | +64 |
Draw By Repetition Bug | Evaluation | 2014 Dec 10 | 27 | 225 | 1813 | +47 |
Passed Pawns | Evaluation | 2014 Dec 09 | 26 | 225 | 1766 | +72 |
Time Management | Search | 2014 Dec 08 | 25 | 231 | 1694 | +24 |
Delay Move Generation Aspiration Window Bug |
Search | 2014 Dec 02 | 23 | 231 | 1670 | +44 |
MVV / LVA Move Order Draw By Insufficient Material Move List Overflow Bug |
Search | 2014 Dec 01 | 22 | 235 | 1626 | +30 |
Tapered Evaluation MG and EG Piece Location |
Evaluation | 2014 Nov 29 | 21 | 234 | 1596 | +107 |
Alpha / Beta Negamax Aspiration Windows Quiescence, Hash Material, Piece Squares |
Baseline | 2014 Nov 25 | 20 | 236 | 1489 | – |
- Subversion source code revision
- Win At Chess position test, 3 seconds per position
- Bullet chess, 2 min / game + 1 sec / move