A mathematical model of the finding of usability problems
@article{Nielsen1993AMM, 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}, year={1993} }
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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