Evaluating the effectiveness of visual user interfaces for information retrieval

viewer 1 Table 6. Misunderstandings of metaphors or system functionality reported by users in de-briefing interviews. Seven users experienced problems with the thesaurus. Only one user didn’t understand the basic hierarchy model, but she and six others had problems with the hierarchy levels and links between them, unevenness of the tree (some sub-branches had more sub-levels than others), the choice of categories and the absence of synonyms. Three users wanted to have their own customised thesaurus. Browser controls which determined the number of clusters were poorly understood, and these users also had problems with the enlarge and move functions. The encoding of relevance in the browser-bullseye metaphor was understood by all users, although the rationale for clusters was not clear for four subjects. The similarity model was not understood by six users and few of them actually used the similarity search command