#2120
"You mean figure 2, page 7?"
Yes, figure 2, my bad.
"you are implicitly assuming that the game-theoretic value is a draw"
++ Yes, I wrote that above: I assume the generally accepted hypothesis that chess is a draw to be true. From that follows that any decisive games contains an odd number of errors, at least 1. The number of decisive games gives the error rate in absolute terms. We do not know what move was the error, but we know it is there. The fact that the draw rate goes up with more time even supports the hypothesis.
To the mathematical nitpickers: I fit
error = a / time^b
and estimate 2 parameters a and b from 2 data points, that is mathematically sufficient but not redundant. In plain English:
time * 60 = error / 5.6
"if the game was a win for White or for Black, following your reasoning we should think that at least one error occurred in all the drawn games"
++ Yes, that is right: if chess were a win for white or even for black, then all the drawn games would contain an odd number of errors, at least 1. That would lead to the odd outcome that more time = more errors.
"Errors might have occurred in all games, independently from the result."
++ That is right, under the hypothesis that chess is a draw a drawn game might contain an even number of errors, at least 2. However at 1 error per 10^5 positions at 60 h/move, the probability of 2 errors would be 1 in 10^10 << 10^5.
#2115
"if errors are not statistically independent, how can you say that P(2nd error | 1st error) ~= P(1st error)?"
++ There is hardly any statistical dependence. If the 1st error allows a checkmate in 1, then that ends the game and there can be no 2nd error, but that is rare. For all practical purposes
P(2 errors) = P(1 error)^2.
I wrote the exact formula with conditional probability
P(error 1 & error 2) = P(error 2|error 1) * P (error 1)
only to avoid mathematical hair splitting.
In computer self play games - many of the errors would be repeated by both sides.
Or - just inferior moves.
More likely positionally inferior than tactically inferior.
Or - just moves the computer is in error assigning as 'superior' where there are in fact many comparable moves.
Computers detecing their own errors?
Basing the error percentage on the computers' own reports of same?
Regarding 'facts and figures' people disagreeing with posts can use the same facts and figures already presented in the posts they're disagreeing with.
There's no 'imperative obligation' to obtain one's own 'peer-reviewed' facts and figures.
Idea: present one's own logical arguments instead of parroting stuff from the net.