Study of Interfaces for Time-Continuous Emotion Reporting and the Relationship Between Interface and Reported Emotion

This paper presents interfaces for reporting emotion in real-time during VR stimuli. Self-reported emotional responses are critical for developing emotion recognition systems. Such responses can vary throughout a stimulus such as 360° video, but most interfaces for reporting emotion are designed to be used after the experience. This reduces the entire experience to a single data point and raises concerns about validity when multiple emotions can be elicited across the stimulus. We introduce and compare user interfaces that allow for real-time emotion reporting throughout the length of the stimulus. Each interface varies on how emotion is physically input by the user and displayed back to them for confirmation. A preliminary study compared five such interfaces, gathering initial impressions, comparing control schemes, and rating intuitiveness. A primary study considered four refined interface designs and compared reporting precision and subjective opinions. Results suggest that a single interface face icon responding to arousal and valence reports and a gradiating color wheel are intuitive, precise, and unobtrusive. More broadly, results indicate the type of rating interface has a significant effect on the given ratings.