Morten Hertzum & Niels Ebbe Jacobsen (2001)
International Journal of Human-Computer Interaction, 13(4), 421-443.
DOI: https://doi.org/10.1207/S15327590IJHC1304_05
Abstract. Hertzum and Jacobsen's empirical finding that any two usability evaluators given the same interface generate problem lists with only ~25% overlap. The single most-cited reference for "use multiple evaluators" recommendations in usability planning.
Tags: methodology evaluator-effect foundational