Why?

To get objective data about users' attention and physical state.

How?

Using specialist hardware such as eye-tracking equipment, eye-tracking glasses or sensors to measure heartrate, skin conductivity or brain activity, can be used to collect objective measurements of users' engagement with a design.

Ingredients

• Specialised bio-metric equipment.
• Access to a trained expert who can help you with setup and interpretation.
• A sense of what can and cannot be concluded from biometric data.
• A quantitative mind-set.

In practice

Eye-tracking is used in addition to standard usability testing to detect problems in the interface. These can be a starting point for interviews. Other biometric measures are used to measure player enjoyment in games or in simulators.

Useful resources

• Universal Methods of Design. (Hanington & Martin, 2012) spends a couple of pages on eye-tracking.In the Dutch version chapter 40. P86-87
• There is a chapter on eye-tracking in Ways of Knowing in HCI (Olson & Kellogg, 2014) p323-348