How Is Harmonic Centrality Calculated?

For a node v, find the shortest directed path from v to every other node u. Add 1 / d(v,u) for each reachable node, where d(v,u) is that shortest path length.

A directly linked node is distance 1 and contributes 1. A node two links away contributes 0.5. Longer paths contribute less. Unreachable nodes contribute zero, so the sum can be computed even when the graph is disconnected.

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