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Abstract

Systems as diverse as genetic networks or the World Wide Web are best described as networks with complex topology. A common property of many large networks is that the vertex connectivities follow a scale-free power-law distribution. This feature was found to be a consequence of two generic mechanisms: (i) networks expand continuously by the addition of new vertices, and (ii) new vertices attach preferentially to sites that are already well connected. A model based on these two ingredients reproduces the observed stationary scale-free distributions, which indicates that the development of large networks is governed by robust self-organizing phenomena that go beyond the particulars of the individual systems.

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We thank D. J. Watts for providing the C. elegans and power grid data, B. C. Tjaden for supplying the actor data, H. Jeong for collecting the data on the WWW, and L. A. N. Amaral for helpful discussions. This work was partially supported by NSF Career Award DMR-9710998.

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Published In

Science
Volume 286 | Issue 5439
15 October 1999

Submission history

Received: 24 June 1999
Accepted: 2 September 1999
Published in print: 15 October 1999

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Authors

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Albert-László Barabási*
Department of Physics, University of Notre Dame, Notre Dame, IN 46556, USA.
Réka Albert
Department of Physics, University of Notre Dame, Notre Dame, IN 46556, USA.

Notes

*
To whom correspondence should be addressed. E-mail: [email protected]

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