We represent all the tuple types 1 X and all the extraction pattern types Y contained in a given corpus through an undirected, weighted, bipartite graph G = (V, E) with vertices V = X ∪ Y and edges E ⊂ X × Y , where an edge (x, y) ∈ E indicates that tuple x occurrs with pattern y somewhere in the corpus.
edge weights are defined through a weight matrix W which holds the weight we use the count of how many times a tuple occurs with a pattern in the corpus and weights for unconnected vertices are zero.