Design and Evaluation of an Auditory Glance at Algebra for Blind Readers

An overview or glance is important in planning the reading process. Such a high-level view is not possible for a blind person when reading by listening. This paper describes the soniication of algebra notation to provide an audio glance to facilitate planning prior to reading. Prosodic cues used in spoken algebra were combined with pre-existing guidelines for earcon design to produce a high-level view of expression structure called algebra earcons. The initial evaluation indicated listeners could recover syntactic information from an algebra earcon and pick an appropriate expression. Some deeciencies were revealed, that were amended and then retested in a second experiment showing an improvement in recognition of syntactic features. Analysis of verbal protocols revealed the level of syntactic information the listeners could retain and recall, and also the strategies used.