  With the recent advancements in intelligent personal assistants (IPAs), their
popularity is rapidly increasing when it comes to utilizing Automatic Speech
Recognition within households. In this study, we used a Wizard-of-Oz
methodology to evaluate and compare the usability of American Sign Language
(ASL), Tap to Alexa, and smart home apps among 23 deaf participants within a
limited-domain smart home environment. Results indicate a slight usability
preference for ASL. Linguistic analysis of the participants' signing reveals a
diverse range of expressions and vocabulary as they interacted with IPAs in the
context of a restricted-domain application. On average, deaf participants
exhibited a vocabulary of 47 +/- 17 signs with an additional 10 +/- 7
fingerspelled words, for a total of 246 different signs and 93 different
fingerspelled words across all participants. We discuss the implications for
the design of limited-vocabulary applications as a stepping-stone toward
general-purpose ASL recognition in the future.
