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Google matrix, dynamical attractors, and Ulam networks
1Laboratoire de Physique Théorique (IRSAMC), Université de Toulouse-UPS, F-31062 Toulouse, France.
Summary
This study models the Google matrix using dynamical systems, revealing networks with web-like properties. Changes in parameters can disrupt PageRank, leading to inefficient search results.
Area of Science:
- Complex Systems
- Network Science
- Dynamical Systems
Background:
- The Google matrix, derived from the Perron-Frobenius operator, models complex networks.
- Dynamical systems with dissipation can exhibit properties analogous to real-world networks like the World Wide Web.
Purpose of the Study:
- To investigate the properties of a Google matrix generated from a coarse-grained Perron-Frobenius operator of a dissipative dynamical system.
- To explore the network characteristics and PageRank behavior of the resulting Ulam networks.
Main Methods:
- Construction of a finite-size matrix approximant using the Ulam method.
- Analysis of the generated directed Ulam networks for scale-free properties and PageRank distribution.
- Comparison of network characteristics with the World Wide Web.
Main Results:
- The Ulam networks exhibit approximate scale-free scaling and degree distributions.
- PageRank demonstrates a power-law decay, similar to the World Wide Web, with sensitivity to the Google parameter alpha.
- Dynamical attractors concentrate PageRank, acting like popular websites.
Conclusions:
- Dynamical systems can generate networks with web-like characteristics.
- Parameter variations in the dynamical map can lead to PageRank delocalization and inefficient search behavior.
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