Erzsébet Ravasz Regan

Home | CVBR | BIDMC | HMS

Hierarchical Organization in Complex Networks

Most real-world networks like the Internet, www, actor network, scientific collaboration networks and cellular networks (metabolism, protein interaction network or genetic networks) are known to have a scale-free degree distribution, with diverging fluctuations in the node connectivity. These networks, however, also show high degrees of clustering. We show that most real networks have hierarchical modularity, where tight small clusters are embedded in larger and looser modules, without having a characteristic cluster scale.

The story:
Publications:
- E. Ravasz, A.-L. Barabási,
  Hierarchical organization in complex networks, Phys. Rev. E, 67, 026112 (2003);
- E. Ravasz, A. L. Somera, D. A. Mongru, Z. N. Oltvai and A.-L. Barabási,
  Hierarchical organization of modularity in metabolic networks, Science, 297, 1551 (2002); Supplementaty Material;
- A.-L. Barabási, E. Ravasz and T. Vicsek,
  Deterministic scale-free networks, Physica A, 299, 559 (2001);
- A.-L. Barabási, E. Ravasz, and Z. N. Oltvai,
  Hierarchical Organization of Modularity in Complex Networks, Lecture Notes in Physics 625, 46 (2003); R. Pastor-Satorras, J.M. Rubi,and A. Diaz-Guilera (eds.), Proc. of the XVIII Sitges Conference on Statistical Mechanics, Sitges, Barcelona, Spain, 2002, Springer, Berlin;
Collaborators:
- Albert-László Barabási, Emil T. Hofman Professor of Physics
  University of Notre Dame, Department of Physics
- Zoltán Oltvai, Professor
  University of Pittsburgh Medical Center, Department of Pathology
- Tamás Vicsek, Professor
  Eötvös Lóránd University, Budapest, Hungary
Presentations:
- Hierarchical Modularity in Complex Networks (Slides)
  News, Expectations and Trends in Statistical Physics - 3rd Next Sigma-Phy International Conference, August 13 - 18, 2005, Kolymbari, Crete, Greece.
- Hierarchical Modularity in Complex Networks (Slides)
  University of Notre Dame, Ph.D. Defence, September 20, 2004, Notre Dame, IN;
- Hierarchical Modularity in Complex Networks (Slides)
  - Brookhaven National Laboratory, Condensed Matter Physics Seminar, February 5, 2005, Upton, NY;
  - Los Alamos National Laboratory, Center for Nonlinear Studies Seminar, November 8, 2004, Los Alamos, NM.
- Hierarchical Modularity in Metabolic Networks (Slides)
  Los Alamos National Laboratory - Arizona Days 2005, January 28 - 29, 2005, Tucson, AZ.
- Hierarchical Organization of Complex Networks (Poster)
  23rd Annual Conference on Networks: Structure, Dynamics and Function, May 12 - 16, 2003, Santa Fe, NM.
- Hierarchical Modularity of Metabolic Networks (Poster)
  Indiana Biocomplexity Symposium, April 22 - 23, 2003, University of Notre Dame, Notre Dame, IN.