Random mover win rate

[xr_a_y]

I add a random mover level to Minic and i'd like to "validate" it.
What is the expected draw/win rate of the random mover playing against itself ?

[Sven]

I would expect a 50% score against itself (i.e., two identical random movers facing each other), with sufficient number of games.

[Guenther]

I add a random mover level to Minic and i'd like to "validate" it.
What is the expected draw/win rate of the random mover playing against itself ?

I expect a draw rate of may be 95% between to rnd movers as they seldomly can enforce wins, no matter how much material difference
inbetween a game.

[hgm]

15.3% wins, 84.7% draws. See http://www.talkchess.com/forum3/viewtopic.php?t=40193 for a subdivision of the draws. (This assumes 3-fold-rep and 50-move draws will be claimed at the first opportunity.)

[JohnWoe]

By Sapeli. Quickly 10_000 games. "-aiw 0" is a random mover.

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sapeli -aiw 0 -aib 0 -game 10000

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...
~~~ Results ~~~
[ Score: 740 - 717 - 8543 [0.50] 10000 ]

Win rate: (740+717)/10000 ~14.57%
Draw rate: 8543 / 10000 ~ 85.43%

Edit: These numbers are for random chess960 positions...

[AlvaroBegue]

After searching the web for about 3 minutes: http://wismuth.com/chess/random-games.html

Enjoy!
Álvaro.

[xr_a_y]

After searching the web for about 3 minutes: http://wismuth.com/chess/random-games.html

Enjoy!
Álvaro.

Yeah I was a bit lazy to ask that here ... sorry guys ... Minic is near this with 86% draw, i'll check deeper tonight.

Thank you all

[hgm]

After searching the web for about 3 minutes: http://wismuth.com/chess/random-games.html

Note that the win rate is slightly larger here than in the Edwards study (both at least a billion games, so the difference is significant): 15.46% vs 15.3%. This is because it uses 6-fold-rep and 75-move rules for declaring draw. Some of the games that would have been draw after 3-fold-rep or 50-move will still result in a checkmate in the mean time.

[xr_a_y]

More details for Minic gives

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    709  0-1 {Black mates}
    644  1-0 {White mates}
   1524  1/2-1/2 {Draw by 3-fold repetition}
   1503  1/2-1/2 {Draw by fifty moves rule}
   4689  1/2-1/2 {Draw by insufficient mating material}
    923  1/2-1/2 {Draw by stalemate}

9992 games (there was 8 disconnection of program ... I'll check for the bug later ...)

White win 6.44%
Black win 7.09%
3fold 15.25%
50move 15.04%
insifficient 46.92%
stalemate 9.23%

I'll have to investigate

[xr_a_y]

Ok last figures after a bug fix

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   1540  0-1 {Black mates}   -> 7.62%
      4  0-1 {White's connection stalls} 
      6  1-0 {Black's connection stalls}
   1498  1-0 {White mates}  -> 7.41%
    497  1/2-1/2 {Draw by 3-fold repetition}  -> 2.46%
   4499  1/2-1/2 {Draw by fifty moves rule}   -> 22.27%
  10883  1/2-1/2 {Draw by insufficient mating material} -> 53.87%
   1272  1/2-1/2 {Draw by stalemate}   -> 6.29%
   
   total 20199

This is near expected ...

Still 10 games went wrong