Author: James Robertson
Date: 16:49:23 10/27/99
Go up one level in this thread
On October 27, 1999 at 17:08:40, Scott Gasch wrote:
>[...]
>>int simplePP[8] = { 999, 55, 33, 23, 16, 12, 0, 0 };
>[...]
>
>This is interesting... a pawn on the seventh for cyclone is 255 (+2.55) while on
>the 6th rank is 128. It also gets a passed pawn bonus of 30 unless it is
>blocked in which case it is 15. King support is 20. Connected passed pawns get
>+3 each additional.
>
>The reason that I used 255 as the 7th rank static bonus is because the engine
>was so cavalier about playing passed pawns until I upped this drastically. A
>good percentage of its losses were due to ignoring a passer and doing other
>stuff until it got to the 6th or 7th rank. It was not until then that the
>program realized it was in trouble.
>
>I justify the 255 score because even an unpromotable but sustainable passed on
>the seventh is tying up at least one minor piece. This is often a winning
>advantage for the side with the pawn threat.
>
>Comments?
>Scott
2.55 seems a little high.... why not just queen the thing and win the minor
piece? :)
Also, I don't think that is the major problem. What could be an issue is when
you give up a piece for that passed pawn. Say you trade your knight for a pawn
to get the passer on the 7th. Sounds like a good deal? 2.55 + 1 > 3, so it makes
sense (to the program). But suppose the opponent has a bishop guarding the
queening square; you can never queen because then you have just traded N+passed
P for B+P.
James
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