Question Chess engine rating- how much variation?

Greyguy1948

Member
Nov 29, 2008
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You have some chess engine rating here: CE rating 40/40

You need something like 300 games to be on the list. But you have to force some kind of variation or...?
If CE 1 starts with white and CE 2 starts next time it could mean 150 identical games.....not very good!
So are they using some kind of random number method?