Using sensor graphs to stimulate recall in retrospective think-aloud protocols

The method of stimulated recall, also called retrospective think-aloud protocol, may draw subjects' attention rather towards their actions and thoughts than to their emotional experience of the search process. This report presents a variation of this method, which aims at eliciting a more extensive verbalization of feelings. In a qualitative study the search activities of seven participants were recorded by a screen recording software, and their electrodermal activity was measured by a skin conductance sensor. Subsequently, a guided interview was conducted, which was followed by the retrospective think-aloud protocol. The protocol consisted of two phases with different stimuli: At first, only the screen recording was displayed to the participants, and afterwards, it was supplemented by a synchronous video of the physiological sensor data. This paper gives a full description of the technique, including recommendations for its practical application. Overall, the presented results show that more events were reported using this method.