My research interests are broad, and currently include complex networks (methods, mechanisms, functions and large-scale structure); statistical and/or machine learning; social networks; power law distributions; the statistical patterns of terrorism; the Internet (structure, routing and security); complex systems; systems biology; macroevolution; biological scaling laws; adaptive and evolutionary computation; self-organization; robustness; mechanism design for network security; game theory.

Much of my core work concerns the development of principled and/or efficient methods for the statistical analysis of the large-scale structure of complex networks. This work leans heavily on ideas from machine learning, computer science, and statistical physics. Although not from the perspective of networks, I also occasionally study the statistics of terrorism. While at the Santa Fe Institute, I also became interested in understanding what generates the enormous diversity in species body mass we observe in the natural world. Finally, many years ago, I worked extensively with genetic algorithms and neural networks. I moved out of those areas partly because of a conviction that our synthetic definitions were fundamentally limited relative to their natural counterparts.

In addition to pure research, I have also advised and/or consulted for a number of businesses on topics including social network analysis and statistical modeling. Since my current focus is on research, however, I try to keep these activities to a minimum.

Press

Evolution and distribution of species body size
LiveScience (July 2008, Clara Moskowitz), SFI Press Release (July 2008), Science News (July 2008).

Hierarchical structure and prediction of missing links
Nature (May 2008, by Sidney Redner), SFI Press Release (May 2008), Roland Piquepaille's Technology Trends (May 2008), Slashdot (May 2008), Science News (June 2008, by Julie Rehmeyer), BioEssays (July 2008, by Natali Gulbahce and Sune Lehmann).

Power-law distributions in empirical data
Nature Physics (May 2008, by Mark Buchanan)

Mapping the Internet
SIAM News (June 2005, by Sara Robinson)

Frequency of severe terrorist attacks
Nature News (February 2005), PhysicsWeb (February 2005), Die Welt (March 2005), Nature News (July 2005), The Economist (July 2005), The Guardian (August 2005), The Why Files (June 2006), American Physical Society (APS) Bulletin (November 2006), and the SFI Bulletin (Spring 2008).

Publications

1. Power-law distributions in empirical data.
   A. Clauset, C. R. Shalizi and M. E. J. Newman.
   Submitted to SIAM Reviews (2007). (Download the code.)

2. A Solvable Model of Species Body Mass Evolution.
   A. Clauset and S. Redner.
   Physical Review Letters, to appear (2008).

3. How many species have mass M?
   A. Clauset, D. J. Schwab and S. Redner.
   American Naturalist, to appear (2008).

4. On the Bias of Traceroute Sampling.
   D. Achlioptas, A. Clauset, D. Kempe and C. Moore.
   Journal of the ACM, to appear (2008).

5. Controlling across complex networks - Emerging links between networks and control.
   A. Clauset, H. G. Tanner, C. T. Abdallah and R. H. Byrne.
   Annual Reviews in Control 32, 183 - 192 (2008).

6. The evolution and distribution of species body size.
   A. Clauset and D. H. Erwin.
   Science 321, 399 - 401 (2008). (preprint version, free reprint via Science)

7. Hierarchical structure and the prediction of missing links in networks.
   A. Clauset, C. Moore and M. E. J. Newman.
   Nature 453, 98 - 101 (2008). (Download the code; Nature version)

8. On the Frequency of Severe Terrorist Attacks.
   A. Clauset, M. Young and K. S. Gledistch.
   Journal of Conflict Resolution 51(1), 58 - 88 (2007).
   (First pre-print appeared online as physics/0502014 in Feburary 2005.)

9. Structural Inference of Hierarchies in Networks.
   A. Clauset, C. Moore and M. E. J. Newman.
   In E. M. Airoldi et al. (Eds.): ICML 2006 Ws, Lecture Notes in Computer Science 4503, 1 - 13. Springer-Verlag, Berlin Heidelberg (2007).

10. Scale Invariance in Road Networks.
    V. Kalapala, V. Sanwalani, A. Clauset and C. Moore.
    Physical Review E 73, 026130 (2006).

11. Molecular modeling of mono- and bis-quaternary ammonium salts as ligands at the a4b2 nicotinic acetylcholine receptor subtype using nonlinear techniques.
    J. T. Ayers, A. Clauset, J. D. Schmitt, L. P. Dwoskin and P. A. Crooks.
    American Association of Pharmaceutical Scientists Journal 7(3), E678 - 85 (2005).

12. Supervised Self-Organizing Maps in QSAR I: Robust behavior with underdetermined datasets.
    Y. D. Xiao, A. Clauset, R. Harris, E. Bayram, P. Santago II, and J. D. Schmitt.
    Journal of Chemical Information and Modeling 45(6), 1749 - 1758 (2005).

13. Finding local community structure in networks.
    A. Clauset.
    Physical Review E 72, 026132 (2005).

14. On the bias of traceroute sampling; or, Power-law degree distributions in regular graphs.
    D. Achlioptas, A Clauset, D. Kempe and C. Moore.
    In Proc. 37th ACM Symposium on Theory of Computing (STOC) (Baltimore, May 2005).

15. Accuracy and Scaling Phenomena in Internet Mapping.
    A. Clauset and C. Moore.
    Physical Review Letters 94, 018701 (2005).

16. Finding community structure in very large networks.
    A. Clauset, M. E. J. Newman and C. Moore.
    Physical Review E 70, 066111 (2004). (Download the code.)

17. Genetic Algorithms and Self-Organizing Maps: A Powerful Combination for Modeling Complex QSAR and QSPR Problems.
    E. Bayram, P. Santago II, R. Harris, Y. D. Xiao, A. Clauset and J. D. Schmitt.
    Journal of Computer-Aided Molecular Design 18(7-9), 483 - 493 (2004).

Pre-prints

1. How do networks become navigable?
   A. Clauset and C. Moore.
   Preprint (2003).

2. Chaos You Can Play In.
   A. Clauset, N. Grigg, M. Lim and E. Miller.
   In Proc. 2003 Santa Fe Institute Complex Systems Summer School (Santa Fe, July 2003).