Zevra chess engine - I went back to development

[Gabor Szots]

I re-uploaded the binaries as they required the library

It seems the old DLL's are good enough.

[sovaz1997]

I made the library not required
It was necessary to install gcc-mingv-w64, it allows you to do static compilation. Old versions use this too, but I have already forgotten in 2 years))

[sovaz1997]

I am releasing a small update to Zevra: Zevra v2.2.1
It includes a slight increase in game strength by ~10 Elo points and fix cppcheck bugs
https://github.com/sovaz1997/Zevra2/releases

[sovaz1997]

New release - Zevra v2.3 r348!
https://github.com/sovaz1997/Zevra2/rel ... /v2.3_r348

This is a big release since I was successfully able to improve the evaluation function using the Texel method.

To do this, I used 100,000 self-play games, from which I took all positions where there are more than 7 pieces and in which the static eval differs from the qsearch by no more than 50 centipawns (it's about 1 million positions). Optimization was carried out for almost all parameters of the evaluation function. The total increase was about 80 Elo points, or even more!

Code: Select all

tc=10+0.1 Hash=16 Threads=1
Games: 1049 W: 518 L: 273 D: 258
ELO: 82.67 +- 18.59 (95%) LOS: 100.00%

Code: Select all

tc=60+0.6 Hash=16 Threads=1
Games: 897 W: 423 L: 201 D: 273
ELO: 87.81 +- 19.29 (95%) LOS: 100.00%

[sovaz1997]

New release - Zevra v2.4 r380!
----------------------------------------

Today I am releasing the new version of Zevra!

Position evaluation has been improved in this version. By optimizing the tuner, I was able to achieve a much faster optimization of the parameters. In this version, PST-tables were added for the endgame and the eval parameters were trained on a new sample of self-play positions (positions were created by self-play Zevra v2.3 with some restrictions).

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tc=10+0.1 hash=16 threads=1
LLR: 2.95 (-2.94, 2.94) [0.50, 3.50]
Games: 1356 W: 690 L: 417 D: 249
ELO: 70.92 +- 16.97 (95%) LOS: 100.00%

[CMCanavessi]

You're on a roll!!

[sovaz1997]

Updated link: https://github.com/sovaz1997/Zevra2/rel ... ix-compile

[Rebel]

Put your engine as new entry for the Gambit Rating List.

Not sure how strong your engine currently is, I estimate ~2700 elo, we will see

Games : 1200

Elo pool : 2696

You can follow the progress on - http://rebel13.nl/b/grl.htm

Page refreshes itself every 30 seconds.

Good luck.

[amanjpro]

Put your engine as new entry for the Gambit Rating List.

Not sure how strong your engine currently is, I estimate ~2700 elo, we will see

Games : 1200

Elo pool : 2696

You can follow the progress on - http://rebel13.nl/b/grl.htm

Page refreshes itself every 30 seconds.

Good luck.

I think it is more like 2500 though

[Rebel]

Zevra 2.4-r380 - 2629

Code: Select all

Gambit Rating List
Running      : gauntlet Zevra_2.4-r380
Time Control : Time control : 40/120
Games        : 1200

Results from file gauntlet-zevra.pgn:

No. Name            Win Draw Loss Unf.  Score Games       %
-----------------------------------------------------------
  1 Zevra 2.4-r380 +363 =213 -624   *0  469.5  1200   39.1%
  2 Fruit 2.1      +114  =34  -52   *0  131.0   200   65.5%
  3 Dumb 1.8       +113  =32  -55   *0  129.0   200   64.5%
  4 k2 099         +109  =38  -53   *0  128.0   200   64.0%
  5 Zahak 5.0      +104  =35  -61   *0  121.5   200   60.8%
  6 Supernova 2.3  +101  =34  -65   *0  118.0   200   59.0%
  7 Monolith 0.4    +83  =40  -77   *0  103.0   200   51.5%

Total Games:    1200
White Wins:      504 (42.0%)
Black Wins:      483 (40.2%)
Draws:           213 (17.8%)
Unfinished:        0 (0.0%)

Estimated ratings for this elo 2696 pool

   # PLAYER            :  RATING  POINTS  PLAYED   (%)
   1 Fruit 2.1         :  2741.4   131.0     200    66
   2 Dumb 1.8          :  2733.7   129.0     200    65
   3 k2 099            :  2729.9   128.0     200    64
   4 Zahak 5.0         :  2705.6   121.5     200    61
   5 Supernova 2.3     :  2692.8   118.0     200    59
   6 Monolith 0.4      :  2639.6   103.0     200    52
   7 Zevra 2.4-r380    :  2629.0   469.5    1200    39