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Subject: Rybka's NPS - one presumption

Author: vladan

Date: 17:47:25 02/16/06

After some hot messages about Rybka’s NPS, I must say something (I was told it
also to my friend Djordje Vidanovic) two months ago.

It is obvious that Rybka’s NPS is not programs real NPS.

It is impossible that program with lowest NPS compared to other engines achieves
depths sand playing strengths above 2850 (or 2900) ELO points, the best of all!

But, I am not sure that Vasik did purposely tune down real NPS. The only
explanation for that will be that he tried to hide Rybka’s origin in some other
public source engines. But Rybka’s plays much different and superior chess,
which implicates me that Vas however did original and good job with his engine.
Of course, as he said, he used ideas, maybe some source portions or solutions
from Fruit, but it is irrelevant if he added (and that is the case) his original
code somewhere, which amplifies playing strings for a major margin. It is not
cloning. If it is, all of us are monkey clones (with 95% same DNK with our
primate relatives :)

Maybe, Vasik counts not all generated nodes, not only terminal (leaf) nodes
without quiescent generated ones. Each terminal node expands to 2-20 q-search
nodes, depended on q-search heuristics (if program has only captures, or checks,
promotions etc.). This presumption explains why Rybka’s NPS varieties and drops
significantly in positions where exsist much checks, or recaptures, and stay
stable at high level in strategically (quit) positions.

Best regards,


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