Usability testing History

In Sears et. [119]:chap.57 the history of usbility tests is traced back to a conference 1982 about 'Human Factors in Computer Systems'. But it needed further 15 years until the book of Shneiderman 'Usability Testing and Laboratories' to clarify the case of usability testing.

Figure 4.2: How to make test terms 'operational' by measuring concrete parameters

In the diagram 4.2 the basic problem of operationalization of terms is illustrated with a matrix (cf. Lauesen (2005)[89]:39). Vertically one can see some terms which address important aspects of usability, and horizontally are methods listed, which can be used for to measure something. Thus, the aspect of ease of learning as linguistic variable can be associated with the measurement how 'fast' the user can solve the task (task time) and counting the number of errors ('problem-count'). If for example a device for solving a specific tasks requires significantly more time and a lot more mistakes are made than with any other device then this can be taken as an indication that the other devices obviously can be learned 'easier'.