title: Projected accuracy metric for the P300 Speller.
abstract: The P300 Speller brain-computer interface (BCI) is a virtual keyboard that allows users to type without requiring neuromuscular control. P300 Speller research commonly aims to improve the system accuracy, which is typically estimated by spelling a small number of characters and calculating the percent spelled correctly. In this paper we introduce a new method for estimating the long-term ("projected") accuracy, which utilizes all available flash data and a probabilistic model of the Speller system to produce an estimate with lower variance and lower granularity than the standard measure. We apply the new method to 110 previously-collected P300 Speller runs to confirm its consistency, and simulate spelling runs from real subject data to demonstrate lower variance on the accuracy estimate for any given amount of data.
authors.forename: Kenneth
authors.initials: K
authors.lastname: Colwell
authors.forename: Chandra
authors.initials: C
authors.lastname: Throckmorton
authors.forename: Leslie
authors.initials: L
authors.lastname: Collins
authors.forename: Kenneth
authors.initials: K
authors.lastname: Morton
mesh_terms: D000465:Algorithms; D062207:Brain-Computer Interfaces; D003143:Communication Devices for People with Disabilities; D004569:Electroencephalography / Q000379:methods*; D018913:Event-Related Potentials, P300 / Q000502:physiology*; D006801:Humans; D015233:Models, Statistical; D015203:Reproducibility of Results; D014584:User-Computer Interface