Chapter 21 - Wizard-of-oz Protoyping

Abstract

A Wizard-of-Oz (WoO) prototype was originally created to allow software makers to test non-existent or experimental speech or haptic interfaces. A secondary goal of WoO is to explore innovation with technologies that may exist but are not yet prototyped, the main example being an unfinished design. This function allows a software maker to test the design direction for an incomplete design to get a proof of concept from users before committing to the design any further. Like all prototyping methods, a WoO prototype is based on suspension of viewers' disbelief. It is a type of interactive prototype where during a usability validation session, the participant thinks that he is interacting with an actual working system using traditionally haptic interaction or natural language input methods. In fact, a member of the software-making team, or a larger scale computer system, is “behind the curtain” interpreting the participant's input directives and feeding back a designed system response. This method has been adapted for use in the early stages of new software feature or product design to simulate a variety of system responses including voice and screen feedback. A human wizard can provide both voice and screen feedback for prototypes of technology, such as a telephone tree user-interface or an agent response system. WoO prototyping usually stops being a focus when system development is well under way and major changes are no longer necessary or possible.