Instead, we rely on particular kernels defined for sets of vectors rather than for a single vector.
we consider kernels of the form (Rubner et al., 2001;Grauman, 2006): where D(P, Q) is the sum of the distances between the elements of the bag of local histograms associated to author P and the elements of the bag of histograms associated with author Q; γ is the scale parameter of K. Let P = {p 1 , .