Horizon effect. The engine only analyzes a certain number of half-moves deep... let's say, 20. Once a move is actually made, it is no longer part of the depth-20 calculation queue, and a new move (leading to a new position) comes over the horizon, possibly changing the eval.
Engine Analysis: Position Evaluation Decreases After “Best Move” is Played
Sort:
Could someone please explain to me how to understand chess engine analysis? Obviously engine evaluation alone is inferior to an understanding of the positions elements.
Going over several games, (example below), it appears that a chess engine will state that the position favors white (or black) by X points. However, after analyzing the position after the “best move”, that advantage sometimes decreases. I.e, in this game, had black not resigned, the engine recommended
...h6
Bd2
However, after analyzing the position after the “best move”, the engine evaluation went down. Shouldn’t the performance of the “best move” make the engine evaluation stay the same instead of decreasing? Or is this simply because an engine may reevaluate the position a few moves deeper after the “best move.” Thanks!
[Site "Chess.com iPhone"]
[Date "07/08/2020 03:48PM"]
[FEN "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1"]
[White "andrewmcevoylee (1521)"]
[Black "HEROBRINECHESS (1488)"]
[Result "andrewmcevoylee wins by Resignation"]
[Termination "(null)"]
1.e4 {29:59} c5 {29:58} 2.c3 {29:58} d6 {29:20} 3.d4 {29:54} cxd4 {29:20} 4.cxd4 {29:53} Nf6 {29:16} 5.Nc3 {29:50} a6 {29:12} 6.Nf3 {29:25} e6 {28:52} 7.Bg5 {29:22} Nbd7 {28:50} 8.e5 {28:41} dxe5 {28:46} 9.dxe5 {28:40} {andrewmcevoylee wins by Resignation}