Who should we ask to test our design? Should that be an experts or rather novices? In 1992 Jakob Nielsen (born 1957 in Copenhagen, Denmark, a leading web usability consultant) made an experiment, in which he used three groups of evaluators: Novice, Double and Double.
- Novice – no experience in usability engineering
- Regular – general usability specialists
- Double – specialists in particular subject of an experiment
It was found that:
- The novices found 22% of the usability problems
- The regulars found 41%
- The doubles found 60%
Nielsen concluded also that:
- Group of 5 novices would find 50% of the usability problems
- 5 regular specialists would find about 80%
- 5 double specialists would find 98% of the problems
