Enter Your Reply The Comment You're Replying To H. G. Muller wrote on Tue, Apr 21, 2009 09:50 PM UTC:I think you misunderstand how engines work. Tree search is simply their way to make plan. That is by trial and error, discarding what does not work, rather than by constructive reasoning selectively producing only that which does work. But the result is exactly the same, and you should not be able to see the difference by watching it play. For Chess there are many different engines, with many different 'personalities'. Yet the search algorithm of every engine is almost exactly te same. It is the evaluation that creates the personality. But the search is necessary to distill strategic traits from transient 'noise' in the evaluation, and thus make the evaluation a meaningful guiding principle. E.g. like havinga passed Pawn on the 7th rank, (in most cases very good), which happens to be untenable and will be lost in 2 moves, making that you are simply a Pawn behind. If engines storm the opponent's King fortress with Pawns, it is because their evaluation has some non-linear term in its King Safety, which penalizes a King as the (say) square of the number of enemy Pawns close to it. They don't have the slightest idea that a checkmate might likely be the result. It is the programmer of the evaluation function that new that, and new that by the time the engine has the Pawns in place, it will likely see a way to push them that breaks down the opponent's fortress and leads to mate within its search depth. The problem with very good engines like Rybka or Fritz is that their 'plans' are completely beyond us mortals, so that we cannot recognize them as such. While the plans we would make in the same position ar in fact hopelessly futile attempts that they easily refute and blow to pieces. This is why it is much more fun to watch games between 'weaker' engines than Fritz. Btw, the 3 Alpaca vs 2 Knights match ended in 47.9% after 402 games. This is really within the margin for equality, so it seem that an Alpaca is nearly exactly 2/3 of a Knight. (i.e. 215 in Kaufman units, which has N=325.) The 2 Guanacos vs 2 Alpacas + Pawn was lost by the Guanacas with only a 37.4% score (434 games). This confirms a Guanaco is worth a lot less than an Alpaca + 0.5 Pawn, perhaps 235. I am now doing 3 Guanaco vs 2 Knights and 2 Alpacas vs 2 Llamas (all as Knight replacements). Edit Form You may not post a new comment, because ItemID MatsNewPieces does not match any item.