{"kind":"user","text":"The betweenness of a node is a measure of centrality in a network. According to this measure, a node is considered to be central if it is responsible for connecting other nodes. In particular, if we assume that communication between a pair of nodes occurs through the shortest path between them, a node that lies on many such shortest paths may possess special leverage within a network. For a given node v, we calculate betweenness in three steps. First, compute the proportion of the shortest paths between two other nodes, t and u, that contain v. For example, two shortest paths occur between the Albizzi family and Tornabuon family, but we want only the proportion that contain v. Second, calculate this proportion for every unique pair of nodes t and u in the graph, excluding v. Third, sum all proportions.\nWhat is the betweenness of the BISCHERI family? Please round the result to the nearest thousandth."}