ABSTRACT
In users’ trialling, users in action are observed to gain information to improve the design at hand. Subjects may be asked to use existing consumer products or design models, ranging from rough sketches to working prototypes. Observations of user activities are the most important data from users’ trialling. An overview of interaction difficulties can help designers focus on certain aspects of the design. However, when information is available on users’ perceptions and cognitions at the moment of experiencing interaction difficulties, users’ trialling can really be a design tool, since causes of difficulties may be traced. Users’ perceptions and cognitions are as a rule not directly observable. The most direct method to elicit perceptions and cognitions is called thinking aloud (TA), which means that subjects are asked to verbalise their thoughts concurrently, while using a product.
