Topological total depth is the cumulative total of the fewest topological depth paths between all pairs of nodes.
Topological total depth
Sources
Hillier , B. & Iida, S. (2005), Network and psychological effects in urban movement, In: A.G. Cohn and D.M. Mark (Eds.): COSIT 2005, LNCS 3693, pp. 475-490.