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Here is the lichess study for the game which is often presented as study.

I am curious here, as to why White is given a strong advantage, even though the material is equal and Black has a lot more active pieces. The Black squared bishop (of Black) is far better poised than White's. The White Squared bishop (of Black) is actively involved in the attack, and the sole knight can swing in easily on c4 square, should a chance arise.

Comparatively, White's minor pieces are underdeveloped. The only advantage I can see White is having is its d-file rook X-raying the Black queen (and potentially an open file)

[FEN "r4rk1/pp2bppp/1np1p3/3q4/3Pb3/1QP3P1/P3PPBP/R1BRN1K1 w - - 0 1"]
Ian Bush
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Soham
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1 Answers1

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The material balance is only temporary. After White goes c4, Black will lose a piece. If Qf5, White has f3 trapping the bishop. All alternatives to Qf5 leave a piece unprotected (for instance c4 Nxc4 Bxe4 Qxe4 Qxc4 +-)

[Event "Chess Calculation: Chapter 1"]
[Site "https://lichess.org/study/VFtoodiL/uG0A42Q9"]
[Date "2021.09.12"]
[Round ""]
[White ""]
[Black ""]
[Result "*"]
[UTCDate "2021.09.12"]
[UTCTime "13:24:02"]
[Variant "From Position"]
[Opening "?"]
[Annotator "https://lichess.org/@/sohamdas"]
[SetUp "1"]
[FEN "r4rk1/pp2bppp/1np1p3/3q4/3Pb3/1QP3P1/P3PPBP/R1BRN1K1 w - - 0 1"]

1.c4 Qf5 
    ( 1...Nxc4 2.Bxe4 Qxe4 3.Qxc4 )
2.f3 *
Ian Bush
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David
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  • Yup, I miscalculated. – Soham Sep 12 '21 at 17:29
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    Well if this is the right answer I suggest you mark it as correct so others don't start worrying about it. – Ian Bush Sep 13 '21 at 07:56
  • While I totally agree with this answer, is this really a +4.7 advantage? The material (bishop vs pawn) gives an advantage of +2. So is the positional advantage an additional +2.7? – frangge Sep 14 '21 at 17:03
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    @frangge Most engines will give an evaluation that corresponds to a higher number than the "material difference". Humans see that White is a bishop up and don't overthink it, but machines keep calculating at great depth and they're probably seeing ways in which the extra piece is used to get even further advantages. – David Sep 14 '21 at 20:50
  • The position is winning, so a perfect computer would probably say “mate in 100” (or whatever). A computer able to look, say, 20 moves ahead might realize that the position and perhaps also the material balance then looks even worse for Black than it does now. – Keba Sep 15 '21 at 13:20
  • Also, I am not sure Stockfish tries to match “1 pawn up” to an eval of +1. After all, in many positions one cannot be simply one pawn up without also altering the position further. (Removing one Black pawn in the starting position gives Black an half-open file, for instance.) Moreover, one can also simply multiply all of Stockfish's evals by 0.7, if one desired to do so, without affecting Stockfish's strength at all. These evals make only sense relative to each other. – Keba Sep 15 '21 at 13:24