The Effects of Number-related Factors on Entry Performance

Number entry is ubiquitous in user interface (UI) design, and in many applications — such as finance, aviation, healthcare — here, mitigating errors is critical. This paper examines the effects of factors such as the type of number (e.g., integer or decimal), number length (i.e., short or long) and display position (i.e., near or far) on entry errors. Until now, these factors have not been explored together. Using a touch-based numeric keypad, we found that number length influenced the probability of committing errors, while the position of presentation did not. Number type impacted user-corrected errors but not uncorrected errors. Number length, number type and display position affected input timings. The findings provide implications for the design of both number representations (e.g., decimal point appearance) and the sociotechnical systems that surround them (e.g., training practice).