Human–Computer Interaction

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Human–ComPuter InteraCtIon

save time. One particular interviewing technique is called the cogni-

tive walkthrough in which the subject (or expert) is asked to “speak

aloud” his thought process (Figure8.5). In this case, the technique

is focused on identifying any gap between the interaction model of

the system and that of the user. We can deduce that cognitive walk-

throughs are fit for evaluation at a relatively earlier stage of design,

namely interaction modeling or interface selection (vs. specific inter-

face design). Another notable variation of the actual usage-based test-

ing is the “Can you break this?” type of testing in which the subject ...