Operator Behavioral Biases Using High-Resolution Touch Input Devices

Abstract

Real-world applications of touch-input technology often do not occur under ideal conditions. Users often must contend with off-axis viewing and nonoptimal positioning, introducing the possibility of vertical or horizontal bias error. In the present study the effects of screen angle relative to line of sight and positioning of targets were examined with a high-resolution (1 pixel or about 1/12 mm) resistive touch input device thought to have minimal parallax. Results replicated earlier findings of Beringer & Peterson (1985) in that a 17-degree declination of the touch surface below orthogonal to line of sight induced a high-touch bias error of 9 pixels (about 3/4 mm) whereas orthogonality of the interface to line of sight virtually eliminated bias. Both software and behavioral compensation strategies are discussed.