Describes a set of experiments performed to investigate whether people can be identified by the way they type. Seven professional typists were given a paragraph of prose to type and the times between successive keystrokes were recorded. The procedure was repeated four months later with the same typists and text. Examination of the probability distributions of the times each typist required to type certain pairs of successively typed letters (digraphs) showed that of the large number of digraphs in most ordinary paragraphs, there are five which, considered together, could serve as a basis for distinguishing among the typists. This finding implies that touch typists appear to have a typing "signature" and that this method of distinguishing typists might provide the basis for a computer authentication system.
Gaines, R. Stockton, William Lisowski, S. James Press, and Norman Shapiro, Authentication by Keystroke Timing: Some Preliminary Results. Santa Monica, CA: RAND Corporation, 1980. https://www.rand.org/pubs/reports/R2526.html.
Gaines, R. Stockton, William Lisowski, S. James Press, and Norman Shapiro, Authentication by Keystroke Timing: Some Preliminary Results, RAND Corporation, R-2526-NSF, 1980. As of January 11, 2023: https://www.rand.org/pubs/reports/R2526.html