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.
This report is part of the RAND Corporation report series. The report was a product of the RAND Corporation from 1948 to 1993 that represented the principal publication documenting and transmitting RAND's major research findings and final research.
Permission is given to duplicate this electronic document for personal use only, as long as it is unaltered and complete. Copies may not be duplicated for commercial purposes. Unauthorized posting of RAND PDFs to a non-RAND Web site is prohibited. RAND PDFs are protected under copyright law. For information on reprint and linking permissions, please visit the RAND Permissions page.
The RAND Corporation is a nonprofit institution that helps improve policy and decisionmaking through research and analysis. RAND's publications do not necessarily reflect the opinions of its research clients and sponsors.