|WikiProject Chess||(Rated Start-class, Mid-importance)|
Need authentic sample game
The example position in the article cannot be from a real game. Black has two bishops on the same color squares, which can only happen via underpromotion, yet black has all eight of his pawns. Thus the position is obviously incorrect. The problem of horizon is a perenial problem in computer search; it should be easy to find examples in the older published literature. --IanOsgood 19:03, 27 November 2006 (UTC)
- Fixed, was just some incorrectly specified piece colors. --IanOsgood 20:06, 1 February 2007 (UTC)
The given position is not a very good example of a horizon problem. A blunder is considered to be caused by the horizon problem if a _small_ further search would prevent it. In this case the search would have to be very large. In this case it seems more like a problem with the evaluation of positions by Fritz. Bouke 13:00, 23 February 2007 (UTC)
- Well, yes, I believe Fritz is very capable and it just got unlucky. But that was the best example I had when I put that in. ~ Jafet (spam) 16:05, 12 November 2007 (UTC)
Isn't the psudocode quiescence_search rather wrong when looking at chess? In chess engines implementations would say:
1) Make an evaluation of the current position (without any search!), assuming this value is save
2) Try capture moves and maybe check giving moves to look whether we can reach more. (using quiescence_search recursively)
Looking at the current "quiete position"-idea of wikipedia you will find:
Assume you have a rather smooth position, your queen can capture a pawn, but your queen will get captured then.
We can detect "quiet position" only if we do that capture moves and decide "no, that pawn-robbery was no good idea!"
If we decide "not a quiet position" because we can capture, we will find, that we will loose our queen. That result would be completely wrong and implementations are not done in chess engines in that way.
You can find a chess-relevant correct description at http://chessprogramming.wikispaces.com/Quiescence+Search