Author: Erik Madsen

No comments

MadChess 3.3 Released

  By

I have released version 3.3 of my chess engine. This release adds static exchange evaluation and integrates it into futility pruning and deferring the search of losing captures. This pushed MadChess’ playing strength above 2800 Elo. In addition, I adjusted formulas used to calculate internal limit-strength engine parameters to be based on 2800 Elo instead of 2600 Elo. If you adjusted any values in the MadChess.AdvancedConfig.json file, please recalculate per instructions included in comments in the file. The engine’s UCI_Elo option still has a max value of 2600, though, because the non-PVS search (alpha / beta window remains open at… Continue Reading

No comments

Do Tough Things

  By ,

I read an interesting post on a computer chess forum last night. It began: Dixondeuxyeux’s Post I thought I would share a few observations that might be of interest to some of you. It was Mark Twain who wrote, “It ain’t what you don’t know that gets you into trouble. It’s what you know for sure that just ain’t so.” I like this adage because it is a humbling reminder that the game we enjoy so much is a brutally honest and cruel taskmaster. It is believed that after the first nine moves of any game, the possible continuations outnumber… Continue Reading

No comments

Missed Blocking Tactic

  By

Lately, I’ve been playing blitz games against MadChess 3.3 (not yet released) to get a feel for how strongly it plays when weakened to my patzer Elo level. Sparring against MadChess helps me calibrate its limit-strength parameters and perhaps glean ideas for classifying more unreasonable inferior moves. My most recent game begins 1.e4 c5 2.Nf3 d6 3.d4 Nf6 4.Nc3 Nc6 5.Bb5 a5 6.Be3 d5 7.e5 Ng4 8.Qd2 Nxe3 9.Qxe3 cxd4 10.Nxd4 Qd7 11.O-O f5 12.e6 Qd6 13.Nxf5 Qxe6 14.Qxe6 Bxe6 15.Nd4 Bd7 16.Rad1 g6 17.a4 Nb4 18.Rfe1 h5 19.Rd2 b6. So far I’ve played well enough for a player of… Continue Reading

No comments

MadChess 3.2.2 Released

  By

I have released version 3.2.2 of my chess engine. This release fixes a bug that caused truncated principal variations when MultiPV > 1. Also, it improves the efficiency of MultiPV search, so it gets deeper faster. This release does not add any features nor playing strength. Testers may substitute this version for version 3.2 without any need to restart or re-run tournaments. You may download x64 and x86 versions of MadChess 3.2.2 from the Downloads page. Install the appropriate version for your computer’s CPU. The x64 binary is the strongest version of the engine. Continue Reading

No comments

MadChess 3.2.1 Released

  By

I have released version 3.2.1 of my chess engine. This release fixes a bug that caused MadChess to report illegal principal variations. That is, PVs that contain illegal moves. To be clear, the bug never caused MadChess 3.2 to crash. Merely to report fantasy lines. I didn’t notice the issue back in January because of my desire to transition from programming chess to playing chess- which involves fighting the urge to tinker with one more engine issue. I did wonder why MadChess occasionally reported truncated PVs in the CuteChess GUI. One factor contributing to my (chosen) ignorance is the CuteChess… Continue Reading