MARK RUBERY CHESS

When we begin to play chess we are told that the value of the different pieces is the following:

Pawn=1, Knight and Bishop=3, Rook=5 and Queen=9 these are naturally approximations of the average values of pieces, since the actual value of a piece is of course dependent on the position. Thus the stronger a player becomes the less dependent he is on the ‘absolute’ values.

The results have been released of a detailed study by International Master Larry Kaufman based on some 300,000 games of chess between players of at least master level that is with Elo-ratings of at least 2300 points. Here are some of the conclusions he arrived at:

‘The average value of the exchange (rook against a knight or a single bishop) is about 13/8 of a pawn.

The advantage for the side with the rook is only 1 and 3/20 of a pawn if the opposing side has the bishop pair. If all the other minor pieces are still on the board, the value of the exchange drops by ¼ of a pawn. If, on the other hand, the queens and a pair of rooks have been exchanged off, it goes up by somewhat more than ¼ of a pawn. The following can serve as a rule: if one side has a rook against a knight and two pawns, then materially it is ¼ of a pawn behind. But if there is a possibility of exchanging major pieces, then it can gain a tiny material advantage. After even more intricate evaluation, it can be added that in the struggle of a rook against a knight the value of the knight increases by 1/16 and that of the rook drops by 1/8 for each pawn over and above the number of 5 on its own side. The modifications operate in reverse for numbers of pawns, which are less than 5.

In the struggle between a rook and two minor pieces, there is generally equality if the side with the rook has 1 or 2 pawns more. Somewhat fewer pawns are required if both minor pieces are knights, and on the other hand 2 pawns are necessary if we are talking about the bishop pair.

The average value of the queen (if the opposing side does not have the bishop pair) is that of a rook, a minor piece and 1½ pawns. The knight is fractionally stronger than the bishop when supporting the rook in its struggle against a queen. The value of a queen and pawn is the same as that of two rooks, when no minor pieces are present. When both sides have 2 or more minor pieces, the queen does not need a pawn to equal the two rooks in value. In the situation of queen against 2 rooks with 5-8 pawns on each side, the advantage of the rooks is a tiny one; when there are at the most 4 pawns per side, the rook has an advantage of approximately ½ a pawn. A queen and half a pawn equals 3 minor pieces.’

WHITE TO PLAY AND MATE IN 3

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r d) e6 n0 ly. Be the chess player, not the chess piece. – Ralph Charell