Zhai, S., Morimoto, C., and Ihde, S. Manual and gaze input cascaded (magic) pointing. In CHI ’99: Proceedings of the SIGCHI conference on Human factors in computing systems (New York, NY, USA, 1999), ACM Press, pp. 246–253. [pdf]
This paper presents an experimental setup where 3 different input mechanisms were compared: pure manual, pure gaze, and a mixed approach. The authors’ first claim is that pure gaze interaction mechanism is unatural as it overload a perceptual channel.
The authors tested the different input mechanisms with 36 subjects. Subjects using gaze only pointing performed worst than those using pure manual pointing mechanism. Best performance were achieved with the mixed approach.
This work explores a new direction in utilizing eye gaze for computer input. Gaze tracking has long been considered as an alternative or potentially superior pointing method for computer input. We believe that many fundamental limitations exist with traditional gaze pointing. In particular, it is unnatural to overload a perceptual channel such as vision with a motor control task. We therefore propose an alternative approach, dubbed MAGIC (Manual And Gaze Input Cascaded) pointing. With such an approach, pointing appears to the user to be a manual task, used for fine manipulation and selection. However, a large portion of the cursor movement is eliminated by warping the cursor to the eye gaze area, which encompasses the target. Two specific MAGIC pointing techniques, one conservative and one liberal, were designed, analyzed, and implemented with an eye tracker we developed. They were then tested in a pilot study. This early- stage exploration showed that the MAGIC pointing techniques might offer many advantages, including reduced physical effort and fatigue as compared to traditional manual pointing, greater accuracy and naturalness than traditional gaze pointing, and possibly faster speed than manual pointing. The pros and cons of the two techniques are discussed in light of both performance data and subjective reports.