Fact · Typing and writing speed
A 2003 CHI paper found shortcomings in the two error statistics then used in text entry research, the MSD error rate and KSPC.
Checked against its source on October 16, 2026
In the source's own words
“We describe and identify shortcomings in two statistics recently introduced to measure accuracy in text entry evaluations: the minimum string distance (MSD) error rate and keystrokes per character (KSPC).”
Metrics for Text Entry Research: An Evaluation of MSD and KSPC, and a New Unified Error Metric, R. William Soukoreff and I. Scott MacKenzie, Proceedings of the ACM Conference on Human Factors in Computing Systems (CHI 2003), pp. 113-120, 2003, Abstract.
Open the original- What it measures
- The paper then proposes an error framework that the field now uses to compare error rates across studies.
- What it does not show
- The paper is about how errors are counted in experiments, not about the speed of individual typists.