(structured heuristic evaluation method)
Masaaki Kurosu 1), Masamori Sugizaki 2), Sachiyo Matsuura 2)
1) Faculty of Information, Shizuoka University
2) Humanonics Research Group, Yamaha Motors Ltd.
Among the various inspection methods, the heuristic evaluation method (HEM) (Nielsen and Molich 1990) and the cognitive walkthrough method ( Polson et al. 1992) are famous and frequently used. These two methods are contrasting in that the former inspects widely but shallowly and the latter inspects narrowly but deeply. But because of the higher flexibility and the higher productivity of the heuristic evaluation method, it is reported that this method is used more frequently than the cognitive walkthrough method (Nielsen 1995). He claims the heuristic evaluation method to be the best of the inspection methods.
This is why we adopted this method as the basis for developing a new inspection method. What we focused on was the number of usability guidelines used in the heuristic evaluation method. In the original heuristic evaluation method, Nielsen proposed 10 guideline items. All the items are important for the user interface design, but when we think of the larger sets of guidelines which are used in the interface design, it should be noted that what he picked up was just a part of the whole set and/or an abstracted superset of the whole guideline items.
Considering the mental process of the usability evaluator when's/he is inspecting the product by the heuristic evaluation method, not the whole set of the usability guidelines but just 10 guideline items are activated in his/her working memory. Because of the small number of the guideline items, there is a possibility that some aspects of the usability may not be actively inspected.
In order to improve the productivity of the heuristic evaluation, it is necessary to increase the number of guidelines presented to the evaluator. But if we simply give him/her a large set of the guideline items at the same time, s/he might be confused because of the capacity of the working memory and we cannot expect the better performance. What we proposed was that the whole guideline items