[Isofarro]

Perhaps the positional sacrifice can be identified by similar means. The most superficial measurement of a position is the material left on the board. So when you compare the superficial measurement to a deeper positional measurement and they are divergent, then we have something positional.

I think one of Kasparov's games against Karpov in the New York portion of one of their World Championship matches involved Kasparov sacrificing a queen for positional compensation on the black side of a King's Indian. It would be interesting to see what this project thinks of that game.