20100921 - Capra, Usability problem description...

Usability problem description and the evaluator effect in usability testing by Capra, Miranda G., Ph.D., Virginia Polytechnic Institute and State University, 2006 , 292 pages; AAT 3207958 My interest: (1) How she developed the 10 UPD? (2) 10 UPD validated? If yes, how? (3) Methodology – 44 evaluators, usability reports, 2 categories of evaluation. (4) Comparison of 2 categories of evaluators – how? (5) Comparison of single evaluator and double evaluator – how? Action: To read the Dissertation again in future. (I have read her Dissertation before.) Previous usability evaluation method (UEM) comparison studies have noted an evaluator effect on problem detection in heuristic evaluation, with evaluators differing in problems found and problem severity judgments. The goals of this research were to develop UPD (usability problem description) guidelines, explore the evaluator effect in UT, and evaluate the usefulness of the guidelines for grading UPD content. Ten guidelines for writing UPDs were developed by consulting usability practitioners through two questionnaires and a card sort. These guidelines are (briefly): be clear and avoid jargon, describe problem severity, provide backing data, describe problem causes, describe user actions, provide a solution, consider politics and diplomacy, be professional and scientific, describe your methodology, and help the reader sympathize with the user. Comments: Capra had established 10 usability criteria (usability problem descriptions). A fourth study compared usability reports collected from 44 evaluators, both practitioners and graduate students, watching the same 10-minute UT session recording. Three judges measured problem detection for each evaluator and graded the reports for following 6 of the UPD guidelines. Comments: Two categories of evaluators were used, i.e. graduate students & usability practitioners. Three judges for each evaluation => why??? There was support for existence of an evaluator effect, even when watching prerecorded sessions, with low to moderate individual thoroughness of problem detection across all/severe problems (22%/34%), reliability of problem detection (37%/50%) and reliability of severity judgments (57% for severe ratings). A simulation of evaluators working in groups found a 34% increase in severe problems found by adding a second evaluator. The final recommendations are to use multiple evaluators in UT, and to assess both problem detection and description when measuring evaluation effectiveness. Comments: Shall I use the concept of multiple evaluators for my UEM?