Exploring Peak-end Effects in Player Affect Through Hearthstone

Peak-end theory suggests that when remembering an experience, people tend to focus on the moments of highest emotional variance and the last moments of the experience. In this paper, we study whether peak-end effects occur in gaming experiences, by comparing real-time to retrospective measurements of player affect. We ran an experiment where each of 26 participants played two games of Hearthstone while their affective state was monitored in real time through self-reporting and facial expression recognition. Additionally, participants submitted a retrospective report on their emotions 24 hours after the experiment took place. Strong correlation was found between the self-reported peak-end and retrospective emotion values, while no correlation was found between the retrospective self-reports and player facial expressions. The results of this study validate that the peak-end rule can be leveraged in order to identify players' retrospective emotions towards a game experience.