An Investigation of the "Tables Versus Graphs" Controversy in a Learning Environment

The study of computer graphics as decision aids has become popular among MIS researchers in the last several years. However, this area of research, like many others in management information systems, has been plagued with methodological problems and contradictory findings. In light of these difficulties, the current study examined the "tables versus graphs" controversy within a learning environment. Seventy-five MBA students were exposed to one of three experimental treatments and asked to develop financial forecasts for fictitious companies over five experimental trials. Following their forecasts for each firm, participants were provided with feedback on the quality of their decisions. The information presentation treatments were as follows:(l) traditional spreadsheet (tabular), (2) graphs using "standard" scaling, and (3) graphs using " nonstandard" scaling. Results suggest that, although graphics may initially demonstrate no advantage over tables, they do show an advantage i f decision makers are repeatedly exposed to the novel format and given feedback on their performance. L. arning will occur even when improper scaling is used. The implication is that the effectiveness of graphics as decision aids depends on practice. Researchers are encouraged to employ repeated measures, or longitudinal, designs when examining the tables-versus-graphs controversy. Introduction display methods. Similar conflicting results have been found when graphs and tables are compared for their How to best display data to decision makers has been a effects on interpretation speed, user preference, and deconcern to MIS researchers since Mason and Mitroff cision confidence (see Ives, 1982; MacDonald-Ross, (1973) first noted the importance of "presentation 1977). Of a total of 7 studies dealing with the impact of mode" in the design of information systems. A large porgraphics on decision quality, only one reports graphs to tion of this research effort has centered on comparing the be superior to tables; 3 conclude that tables are superior relative effectiveness of tables and graphs for the support to graphs, and 3 have found no difference between the of problem solving activities in business settings. Interest two formats (see DeSanctis, 1984). in "tables versus graphs" comparisons has intensified during the past few years as sophisticated, easy-to-use Why is it that computer graphics are not proving to be graphics technology has become incorporated into decimore useful as tools for supporting decision making? sion support systems. The underlying assumption in Several investigators who have found graphs to be fairly these studies is that graphics should facilitate clearer perineffective in improving decision quality have postulated ception of data relationships and trends over tables. that learning must occur before graphical output becomes meaningful to people (c.g., Lusk & Kersnick, 1979; The empirical research dealing with the effectiveness of Vernon, 1946). Business data traditionally has been disgraphs as decision aids has been quite controversial. played in tabular form. Consequently, decision makers Several studies have found graphs to be easier to interpret simply lack the experience needed to properly interpret than tables; others have found the reverse; and still others novel formats. This argument implies that practice in report no difference in interpretation accuracy for the two viewing graphs might improve their meaningfulness to