Observer Perceptions of Overall System Quality – the Lake Wobegon Effect
Thomas J. Smith · Proceedings of the Human Factors and Ergonomics Society Annual Meeting · 2015
Objective: For three different system categories—fabricated artifacts, built environments, and software interfaces, to compare and contrast observer rankings of the overall quality of a selected topic or artifact pertaining to that category, relative to rankings of the quality of different specific attributes of the same topic. Method: A paired samples t-test was applied to ascertain the degree of statistical similarity between the overall quality rankings, and the average specific attribute quality rankings. Result: For each of the three system categories, the grouped average for overall quality rankings is higher than the grouped average for averaged specific attribute quality rankings. Conclusion: Two alternative interpretations of the results are offered, informed by either Gestalt psychology or by neurobiological reference to cognitive versus affective decision-making. Understanding of the basis of the findings will require further research. Application: Usability analysis assumes that evaluating the quality of specific attributes of a selected design will predict overall design quality. It can be argued that findings reported here call into question widely accepted assumptions about the general utility of usability analysis.