Artificial Intelligence and Law

, Volume 26, Issue 1, pp 23–47 | Cite as

Network approach to the French system of legal codes part II: the role of the weights in a network

  • Romain BouletEmail author
  • Pierre Mazzega
  • Danièle Bourcier
Original Research


Unlike usual real graphs which have a low number of edges, we study here a dense network constructed from legal citations. This study is achieved on the simple graph and on the multiple graph associated to this legal network, this allows exploring the behavior of the network structural properties and communities by considering the weighted graph and see which additional information are provided by the weights. We propose new measures to assess the role of the weights in the network structure and to appreciate the weights repartition. Then we compare the communities obtained on the simple graph and on the weighted graph. We also extend to weighted networks the amphitheater-like representation (exposed in a previous work) of this legal network. Finally we evaluate the robustness of our measures and methods thus taking into account potential errors which may occur by getting data or building the network. Our methodology may open new perspectives in the analysis of weighted networks.


Weighted network Structural measures Graph Legal code Codified legal system Communities 



We are very grateful to Mme Elisabeth Catta, Rapporteure for the Higher Commission for Codification, for her interest in our work and for her helpful comments. This study was funded by the Réseau Thématique de Recherche Avancée (RTRA) Sciences et Techniques de l’Aéronautique et de l’Espace ( in Toulouse, France (MAELIA project - Statistical properties of networks have been computed with R and the library igraph (


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Copyright information

© Springer Science+Business Media B.V. 2017

Authors and Affiliations

  • Romain Boulet
    • 1
    Email author
  • Pierre Mazzega
    • 2
  • Danièle Bourcier
    • 3
  1. 1.Univ. Lyon, Jean Moulin, iaelyon, Magellan Research CenterLyonFrance
  2. 2.UMR5563 Geosciences Environment Toulouse, CNRS, University of ToulouseToulouseFrance
  3. 3.CERSA CNRS, Université de Paris 2ParisFrance

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