Skilled Users Interpretation of Visual Displays
1996 (English)Report (Other scientific)
In field studies of decision makers at work we had observed that skilled users seemed to recognize patterns in familiar displays and that they used these as a clue in the decision making task. In four experiments we have assessed and modelled the time required to search and pick out decision relevant information from a screen display. A model of serial self-terminating search gave a good description of trained performance in all of the studied tasks. If, however, the displays exhibited some kind of pattern, then the users learned to exploit that and adopted a different and more effective scanning strategy. The resulting performance could be described by a modified model that took pattern recognition into account. In a fifth experiment, the models from Experiment 1-4 were used to make an accurate prediction of the search time in the task of judging complex medical data. A screen layout that supported a scanning strategy based on pattern recognition was searched in about half the time compared with a similar layout that only supported serial search. The results show that the effect of pattern recognition on search time is stable enough to enable detailed prediction, and large enough to have practical consequences. The implications of the present findings are that rather small changes in a display design, can have substantial effects on the search time for a frequent user. This should be considered when designing displays for applications where users address similar screen displays hundred of times each day; for example in intensive care, process control or office work.
Place, publisher, year, edition, pages
, Report no. 63/96 from Uppsala University Center for Human-Computer Studies, Uppsala, Sweden. 1996.
IdentifiersURN: urn:nbn:se:uu:diva-31879OAI: oai:DiVA.org:uu-31879DiVA: diva2:59777