The New Palgrave Dictionary of Economics

2018 Edition
| Editors: Macmillan Publishers Ltd

Small-World Networks

  • Duncan J. Watts
Reference work entry


The ‘small-world hypothesis’ expresses the idea, long an article of popular belief, that every individual in a given population can reach every other via some ‘short’ chain of intermediaries. Exactly what is ‘short’, how individuals ‘reach’ one other, and how the hypothesis, if true, relates to the structure of social networks are all qsts on which recent progress has been made. Here I describe the genesis of the hypothesis, discuss supporting experimental evidence, and explore some recent mathematical models of small-world networks.


Small-world hypothesis Small-world networks 

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© Macmillan Publishers Ltd. 2018

Authors and Affiliations

  • Duncan J. Watts
    • 1
  1. 1.