Employing Number-Based Graphical Representations to Enhance the Effects of Visual Check on Entry Error Detection

Number entry is a mundane and error-prone task. To find errors, users often rely on visual checks to compare the differences between their instructions and the numbers they have actually input, a task that is difficult for users to do accurately. We therefore propose the use of number-based graphical representations (GRs) as a complement to conventional numeric representations (NR) to enhance visual checks, so users can examine both GRs and NRs to detect errors. We conducted two experiments to explore the issues raised. Experiment 1 examined the effects of GRs and NRs on representation difference detection (i.e. checking if two GRs or NRs are identical). The two representations had a comparative performance by time and error rate. In Experiment 2, we investigated the performance of GRs and NRs with number entry tasks. While extending the task time (increased by 38%), number entry with GRs resulted in significantly fewer errors than without GRs (decreased by 60%). Participants also had a high preference for number entry with GRs. Therefore, the proposed technique is promising for number entry error reduction, and that in safety critical applications improved safety can be achieved.