A mathematical model of the finding of usability problems

  title={A mathematical model of the finding of usability problems},
  author={Jakob Nielsen and Thomas K. Landauer},
  journal={Proceedings of the INTERACT '93 and CHI '93 Conference on Human Factors in Computing Systems},
  • J. NielsenT. Landauer
  • Published 1 May 1993
  • Computer Science
  • Proceedings of the INTERACT '93 and CHI '93 Conference on Human Factors in Computing Systems
For 11 studies, we find that the detection of usability problems as a function of number of users tested or heuristic evaluators employed is well modeled as a Poisson process. [] Key Result For a “medium” example, we estimate that 16 evaluations would be worth their cost, with maximum benefit/cost ratio at four.

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