Ticker: An Adaptive Single-Switch Text Entry Method for Visually Impaired Users

• Published in: IEEE transactions on pattern analysis and machine intelligence Vol. 41; no. 11; pp. 2756 - 2769
• Main Authors: Nel, Emli-Mari, Kristensson, Per Ola, MacKay, David J. C.
• Format: Journal Article
• Language: English
• Published: United States IEEE 01.11.2019; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: accessibility; Adaptation models; Auditory system; augmentative and alternative communication; Bayesian inference; Computer simulation; Delays; Interaction models; Noise; People with disabilities; Probabilistic logic; Scanners; Scanning; Single-switch systems; Statistical analysis; Statistical inference; Statistical models; Switches
• ISSN: 0162-8828; 1939-3539; 2160-9292
• DOI: 10.1109/TPAMI.2018.2865897

Ticker is a probabilistic stereophonic single-switch text entry method for visually-impaired users with motor disabilities who rely on single-switch scanning systems to communicate. Such scanning systems are sensitive to a variety of noise sources, which are inevitably introduced in practical use of single-switch systems. Ticker uses a novel interaction model based on stereophonic sound coupled with statistical models for robust inference of the user's intended text in the presence of noise. As a consequence of its design, Ticker is resilient to noise and therefore a practical solution for single-switch scanning systems. Ticker's performance is validated using a combination of simulations and empirical user studies.