how does computer evaluation work??

Hello I wanted to know how computer evaluation works in terms of numbers say for instance Rybka show me a position and t evaluations show's +79 is this really good a slight edge or something else and what is the evaluation for black -79 does this mean black is really good a slight edge etc... ? Thanks greatly apprieciated.

The evaluations are measured in centipawns, so a +.79 evaluation means white is up by almost a pawn.

Hi Chessmaster102

Don´t know Rybka, so don´t understand about those +79 and –79 you mention. In fact, have never seen a chess computer evaluation.

The only thing I can tell you is this. Since the start of chess via Internet, which makes postal chess rather rapid, and features like analysis and similar, chess computers have lost interest. They are good only to play a while. . . but not much learning (or teaching, as you prefer).

Of course, no doubt playing chess computers is a darn good training method (aleatory we could say, but a good "sparring").

Coming to your point. Do not forget that the programas you find in chess computers have been made by "human minds". OK. I agree. Super genious minds. . . super GMs, but human minds. . . How are you to know that that 79 results (after all) from having prefered to play with the bishops rather than with the knights? Or that the writer(s) prefers a game aimig to pawns endings and so enjoys getting rid of important pieces?

The mathematical (cybernetic) idea behind those programs is, for a given position, to assign values to each piece according to the positión of ALL OTHER pieces for ALL THE POSIBLE COMBIMATIONS THAT CAN BE MADE. . .

. . . and here comes the granddess of computers in chess (and other activities). . .that by the time you study a couple of positions, the computer have studied thounsands of them.

And so come the "levels" of play of the computer. A level of play of 30 seconds is far better than one of ten seconds. . . but not in a straight proportionality (3 times better in this case). . . in an exponential proportionality, much greater than the straight one.

That is why computers think better than humans. . . because have studied more combinations. . and chances are that if they studied more cases, they should be better off.

Perhaps I did not help towards your post. I only want to point that we should not be too concerned with the chess computer´s opinion and stick to our human condition of beiug

By and luck.