MadChess 3.0 Beta Build 075 (Eval Param Tuning)

I ported my particle swarm tuning code from MadChess 2.x to MadChess 3.0 Beta, then simplified and improved it. My code uses the Texel tuning technique described by Peter Österlund in a TalkChess forum post. I improved my particle swarm algorithm in the following manner. Simplified update of evaluation parameters via EvaluationConfig class. Run the Iterate method of each ParticleSwarm on the .NET Core threadpool instead of using dedicated threads. Locate global best particle (among all particle swarms) and update particle velocities after all Iterate methods have completed. This eliminates need to synchronize reads and writes of global state via… Continue Reading

MadChess 2.2 Released

I have released version 2.2 of my chess engine. Source code and Windows binaries are available on the Downloads page. MadChess 2.2 is about 50 Elo stronger than version 2.1. It includes the following improvements. Added best move estimation. In principal variations where the cached position does not specify a best move, MadChess will search at reduced depth to obtain a best move. Then it completes the full depth search, searching the best move first. This is called Internal Iterative Deepening (IID) in other engines, though I find the name misleading. It’s recursive but not iterative. Added endgame piece location… Continue Reading