| Preece et al. define testing or evaluation as the | | | | 'real problems, not imaginary ones'. (ibid. 2002:321) |
| process of 'systematically collecting data that informs | | | | Evaluation with users underpins a user-centred |
| us about what it is like for a particular user or group of | | | | approach to design. Preece et al. refer to Gould and |
| users to use a product for a particular task in a certain | | | | Lewis who identify three main characteristics of this |
| type of environment'. (Preece et al. 2002:317) That is to | | | | approach. There is an 'early focus on users and tasks' |
| say that it is a process where the interface is tested | | | | which means understanding users and tasks through |
| against the practices and needs of the user. (Faulkner | | | | observation and analysis, whilst actively involving users |
| 1998:109) Evaluation is important in design as it aims to | | | | from the early stages of design. 'Empirical |
| 'eradicate any problems that may be present in a | | | | measurement' gauges the performance and reactions |
| system'. (ibid. 1998:124) Evaluation and amendment of | | | | of users to storyboards and paper prototypes for |
| the design at various stages of development helps the | | | | example, in the early stages of development and |
| designer to verify that the product is suitable for the | | | | subsequently to software prototypes or simulations for |
| users' needs, that they can use the product and indeed | | | | example. Another feature of a user-centred approach |
| they like the product. (Preece et al. 2002:317-319) | | | | is 'iterative design' characterised by cycles of 'design, |
| Preece et al. refer to Tognazzini who asserts that | | | | test, measure and redesign'. (Preece et al. |
| evaluation also ensures that the design team focus on | | | | |