Nature 437, 951 (13 October 2005) | doi:10.1038/437951e; Published online 12 October 2005

System to rank scientists was pedalled by Jeffreys

A. W. F. Edwards1

  1. Gonville and Caius College, University of Cambridge, Cambridge CB2 1TA, UK


Jorge Hirsch's index for measuring research achievement, as described in your News Story "Index aims for fair ranking of scientists" (Nature 436, 900; 2005) was used by the geophysicist Harold Jeffreys for recording his cycling prowess, n being the highest number of days on which he had cycled n or more miles. I think he told me, some 35 years ago, that his n was 70 and that he first had the idea from his fellow cyclist, the astrophysicist Arthur Eddington.

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