, a sample , and a feature , the C-Shapley estimate of order k on a graph is given by : where denotes the set of all subsets of that contain node , and nodes that are connected in . ℙm x i G Ck (i) k (i) i G ̂ ϕk x (i) = ∑ U∈Ck (i) 2 (|U| + 2)(|U| + 1)|U| mx (U, i) original Shapley value : ϕx (i) = ∑ S∋i,S⊆[d] 1 ( d − 1 |S| − 1) mx (S, i)