Entropies of complex networks with hierarchically constrained topologies
  The entropy of a hierarchical network topology in an ensemble of sparse random networks with "hidden variables" associated to its nodes, is the log-likelihood that a given network topology is present in the chosen ensemble.We obtain a general formula for this entropy,which has a clear simple interpretation in some simple limiting cases. The results provide new keys with which to solve the general problem of "fitting" a given network with an appropriate ensemble of random networks. 
Ginestra Bianconi, Anthony C.C. Coolen and Conrad J. Perez Vicente