On Apr 29, 5:39 pm, (Chris Mattern) wrote:
In article .com,



raylopez99 wrote:
On Apr 27, 2:49 pm, "Inconnux" wrote:


To properly analyze the world champions
you would need to use a program that is atleast equal in strength to
these champions. Crippled Crafty just doesn't cut it... now if they
used Rybka for analysis I wouldn't have any problem
with the study.

J.Lohner

Not true at all. Crafty could easily tell you which programs far
stronger than itself played the most perfect chess. This is not
debatable.

Not only is it debatable, it's not true.

No it is true.


For instance, the winning program between two chess
programs playing each other by definition will produce at least one
less error than the losing program--and Crafty could, at some point,
appreciate this.

Er, how? If Crafty is less able than the losing program, how
can it reliably see the error the losing program couldn't?


Easy. The evaluation function of Crafty will indicate that the losing
program, which we've said is much stronger than Crafty, scored, over
the length of the game, worse than the winning program.

To give a simple example: two programs, A and B, both much stronger
than Crafty, play a slugfest game that extends over 100 moves. Play
is evenly matched, and Crafty scores both programs about the same up
to this point. However, at the 101st move, program A sees a winning
10 move combination--that happens to be a mating net-- that is just
outside the 8 move horizon of program B. Program A enters into the
combination and after say the 5th move, Crafty, with a mere five move
chess horizon, also "sees" the winning combination. Of course program
B also has seen this combination wins after the second move but let's
say is programmed with a contempt factor not to resign but to play to
the end. Program A checkmates program B after the 10 move
combination. Crafty will reward Program A and penalize Program B for
this play, even though it is much weaker than either program A or B.


--
Christopher Mattern


Do you really work for Sun? What a disaster that stock has been.
Back to work for you.

RL