title: Evaluating pictogram prediction in a location-aware augmentative and alternative communication system.
abstract: This study compared the performance of two statistical location-aware pictogram prediction mechanisms, with an all-purpose (All) pictogram prediction mechanism, having no location knowledge. The All approach had a unique language model under all locations. One of the location-aware alternatives, the location-specific (Spec) approach, made use of specific language models for pictogram prediction in each location of interest. The other location-aware approach resulted from combining the Spec and the All approaches, and was designated the mixed approach (Mix). In this approach, the language models acquired knowledge from all locations, but a higher relevance was assigned to the vocabulary from the associated location. Results from simulations showed that the Mix and Spec approaches could only outperform the baseline in a statistically significant way if pictogram users reuse more than 50% and 75% of their sentences, respectively. Under low sentence reuse conditions there were no statistically significant differences between the location-aware approaches and the All approach. Under these conditions, the Mix approach performed better than the Spec approach in a statistically significant way.
authors.affiliation: a Instituto Politécnico de Beja, Campus do Instituto Politécnico de Beja , Beja , Portugal.
authors.forename: Luís Filipe
authors.initials: LF
authors.lastname: Garcia
authors.affiliation: b INESC ID Lisboa, Instituto Superior Técnico, Universidade de Lisboa , Lisboa , Portugal.
authors.forename: Luís Caldas
authors.initials: LC
authors.lastname: de Oliveira
authors.affiliation: b INESC ID Lisboa, Instituto Superior Técnico, Universidade de Lisboa , Lisboa , Portugal.
authors.forename: David Martins
authors.initials: DM
authors.lastname: de Matos
mesh_terms: D000293:Adolescent; D000328:Adult; D003143:Communication Devices for People with Disabilities; D003147:Communication Disorders / Q000534:rehabilitation; D003198:Computer Simulation; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008297:Male; D014584:User-Computer Interface; D055815:Young Adult
keywords: adaptive interfaces; communication rate; dynamic screen interfaces; location-awareness; pictogram prediction