18. The system of claim 17 , wherein h ij = exp ⁢ ( -  f ⁡ ( x i , w ) - f ⁡ ( r ⁡ ( j ) , w )  2 2 ⁢ σ 2 ) , where x i =a feature vector containing evaluated feature information for document i of the set of documents, r(j)=the j-th document in the ranking induced by the relevance function, w=a coefficient vector, f(x i , w)=the relevance function evaluated on document i, and σ=a smoothing length-scale parameter.
19. The system of claim 18 , further comprising: a relevance function tester configured to test the relevance function having the values for the one or more coefficients determined by the relevance function tuner.