# Patterns of link reciprocity in directed networks.

@article{Garlaschelli2004PatternsOL, title={Patterns of link reciprocity in directed networks.}, author={Diego Garlaschelli and Maria Immacolata Loffredo}, journal={Physical review letters}, year={2004}, volume={93 26 Pt 1}, pages={ 268701 } }

We address the problem of link reciprocity, the nonrandom presence of two mutual links between pairs of vertices. We propose a new measure of reciprocity that allows the ordering of networks according to their actual degree of correlation between mutual links. We find that real networks are always either correlated or anticorrelated, and that networks of the same type (economic, social, cellular, financial, ecological, etc.) display similar values of the reciprocity. The observed patterns are…

## 348 Citations

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