Users' Performance and Preferences for Online Graphic, Text and Auditory Presentation of Instructions

Traditional technical manuals consist primarily of text sup- plemented by tabular and graphic presentation of informa- tion. In the past decade technical information systems have increasingly been authored for presentation on computers instead of on paper; however a stable set of standards for such manuals has yet to evolve. There are strong beliefs but little empirical evidence to guide standards development within companies producing Interactive Electronic Techni- cal Manuals (IETMs). The current study compares three different modes of in- struction presentation for mechanical assembly tasks (graphic, text, and auditory), using a Wizard of Oz para- digm. Study participants preferred graphically-presented information and they completed the tasks fastest using this presentation mode. We found no significant difference in performance or preference between text and audio condi- tions. Nevertheless users indicated a clear desire that graphic presentation be supplemented by other modes. Study results will be useful for designers of multi-modal interfaces for online instruction systems.