We consider in particular the scoring function: where h a and h p are feature representations, nonlinear functions of the features φ a and φ p (respectively), and g is a function of these representations.
we define and we take g to either be the identity function, in which case the above model is analogous to s lin+ but defined over non-linear feature representations, or to be an additional hidden layer: g( hp(x,y) + b).