thesisTechnological innovations have increased the ability to collect and store information. However, these innovations potentially create a psychological problem because the increasing amounts of information must be managed within the still limited human cognitive processing capacity. One common data visualization approach to improve information search is the concept of increased bottom-up stimulus-driven saliency to guide the user. But is increasing the salience of an item enough to produce a sufficient, efficient search with high decision accuracy? How does increasing the salience of an item without regard to its relevance affect the search for information? Is there a difference between lists and tag clouds and what role does the system context; play? To answer these questions we adapted the concepts of the Wason selection task (WST) and considered the propositional logic values of P, Q, not P and not Q, to analyze search sufficiency, efficiency, decision accuracy and search patterns. We found that the incongruence or congruence of salience and relevance can impede or support the search for information. However, increasing the salience of relevant items is not enough to insure a sufficient or efficient search with an accurate decision. The search for information is affected by interactions between the display format, the system context; and the congruence conditions
