Stockfish Reverts 5 Recent Patches

[Michel]

• The validity of the pentanomial model can be verified by simulation.
  https://github.com/vdbergh/pentanomial
• Concerning short tests: there are various things to consider, notably:
  • Fishtest Elo bounds are no longer BayesElo.
  • The stopping time distribution for an SPRT has long tails.
  • The great majority of patches submitted to Fishtest are at best neutral (the Elo prior was measured some time ago to be ~ N(-1,1)).

[Michel]

I wrote a simple multi-threaded C version of the pentanomial simulator.

https://github.com/vdbergh/simul

Everything in a single C file. As it is much much faster than the Python version one can see better how accurate the implementation is.

[Michel]

I wrote a simple multi-threaded C version of the pentanomial simulator.

https://github.com/vdbergh/simul

Everything in a single C file. As it is much much faster than the Python version one can see better how accurate the implementation is.

Now with a decent README.md!

[Jouni]

SF is so strong, that today all changes need almost astronomical number of games to pass. In good old days it was 100-200 games and engine was better .