Viewing Distance Estimation in Eye Tracking Based on Self-Point Estimation on Map

This paper presents a method to estimate viewing distance from the self-point to the fixation point in eye tracking. This method is designed for outdoor experiments of human visual attention using an eye tracker. This method uses positions on a map and viewing angles of the eye tracking. We performed an experiment in which participants wearing an eye tracker looked at a pole 19.9 m distant and this viewing distance was estimated by the proposed method. Standard deviation of the relative error was less than 1.6 percent and its mean was less than 0.8 percent.