Impacts of decision task, data and display on strategies for extracting information

Decision tasks often require the extraction of information from displays of quantitative data. This paper investigates how people extract information from any one of several common displays by analysing the match between display, decision task and data. We posit two kinds of activity: first, the formulation of an appropriate extraction strategy and second, the execution of that strategy. We then develop a model of strategy formulation. We hypothesize that with matched designs a higher proportion of subjects use common strategies characterized by less time to formulate, less time to execute and more accurate decisions. A laboratory experiment using a new technique of graphical protocol analysis supported these hypotheses. Moreover, the experiment demonstrated how changes in display, decision task and data alter the way people select decision strategies. This suggests new opportunities for designing more effective human—computer interfaces. ( 1998 Academic Press Limited