Author: Mike Byrne
Date: 16:22:12 02/18/04
Go up one level in this thread
On February 18, 2004 at 18:21:10, Bruce A Rhoades wrote:
>Quick scenario:
>
>I created a personality. I then cloned the personality to make a second
>identical one.
>
>I am having them play a match against each other. They have played 48 games so
>far.
>
>The score
>personality 1: 21 wins
>personality 2: 10 wins
>the remaining games being draws
>
>The strange part:
>How can two identical personalities have such a difference in score?
>
>I thought perhaps I had erred and they are not identical. I did a CRC check on
>the two .cmp files, and they match.
It's called "chance". After reading your post, I wrote a little program using a
random number generator. The numbers drawn were were 1 through 1000. Anything
between 1 and 400 was assigned a draw (1/2) score, anything between 400 and 700
was assigned loss(1) score. Anything above 700 up to 1000 was assiged a won
(1)score .
I went through a series of 48 round results - many people think 48 rounds are
plenty. The expected outcome is that each 48 rounds would be about even.
W L D
1 10 15 23
2 11 18 19
3 19 13 16
4 16 14 18
5 14 16 18
6 11 11 26
7 13 17 18
8 9 19 20
9 15 14 19
10 16 11 21
11 17 14 17
12 16 17 15
13 15 19 14
14 6 18 24
That last cycle of 48 "games: is interesting.
Conclusion:
Even when two programs are dead even, there could be sufficient randomness that
even a match of 48 games might provide the user a result that looks anything but
even.
That randomness is called "chance" or luck. Although chess is not a game of
chance ,there is a element of chance when two evenly match programs play each
other (as you just proved). That is why authors of stronh chess programs
dislike short "swiss" touranament - as they know they coould get unlucky and
lose. The longer the tournament, the more games played, the greater likelihood
you will crown the best program as the champion.
Search "Fritz 'Deep Blue' 1995 'Hong Kong'" on google to read about the lucky
Fritz program that beat the unlucky and stronger chess program "Deep Blue" in a
tournament that is still talked about today.
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