Wizard of Oz
The Wizard of Oz technique enables unimplemented technology
to be evaluated by using a human to simulate the response
of a system.
This technique can be used to test device concepts and techniques
and suggested functionality before it is implemented.
The "wizard" sits in a back room, observes the
user's actions, and simulates the system's responses in real-time.
For input device testing the "wizard" will typically
watch live video feeds from cameras trained on the participant's
hand(s), and simulate the effects of the observed manipulations.
Often users are unaware (until after the experiment) that
the system was not real.
The "wizard" has to be able to quickly and accurately
discern the user's input, which is easiest for simple for
voice input or hand movements. The output must also be sufficiently
simple that the "wizard" can simulate or create
it in real time.
The Wizard of Oz technique can provide valuable information
on which to base future designs. It can:
- gather information about the nature of the interaction
- test which input techniques and sensing mechanisms best
represent the interaction (so that subsequent effort developing
or adapting sensing technologies is appropriately directed)
- test the interaction of a device before building a functional
- find out the kinds of problems people will have with
the devices and techniques
- investigate aspects of the products form such as visual
affordance (whether the product shows how it can be used)
testing in user input device design Timothy Griffin
of Oz MARBLE project