Standard Article

U-Shaped Distribution

  1. Brian S. Everitt

Published Online: 15 JUL 2005

DOI: 10.1002/0470011815.b2a15171

Encyclopedia of Biostatistics

Encyclopedia of Biostatistics

How to Cite

Everitt, B. S. 2005. U-Shaped Distribution. Encyclopedia of Biostatistics. 8.

Author Information

  1. Institute of Psychiatry, London, UK

Publication History

  1. Published Online: 15 JUL 2005


This is a probability distribution or frequency distribution shaped roughly like the letter U, with highest frequency at the two extremes, although not necessarily symmetrically. The variables are sometimes called bounded scores.


  • probability;
  • frequency;
  • bounded score;
  • Wilcoxon–Mann–Whitney