Strength of Component Principles Determining Direction-of-Turn Stereotypes for Horizontally Moving Displays

Abstract

Direction of turn stereotypes were determined for horizontally moving displays with various knob locations, combined with top and bottom scales which either increased or decreased to the right and having neutral or directional indicators. Equations were written for the strength of the stereotype (proportion of clockwise movements) in terms of the direction predicted by various principles; clockwise to increase, clockwise to the right, clockwise away, scale-side and Warrick's. Solution of these equations for the case of knobs located at the sides of the display showed that the strength of the stereotype was largely determined by “clockwise to right” principle (about 51% and 93% respectively for groups of engineering and psychology students). The corresponding figures for the “scale-side” principle of Brebner and Sandow were 16% and 2%. Knobs located either on the top or bottom of the display have movement stereotypes determined by Warrick's principle (54% and 15% for engineering and psychology groups) and “clockwise to the right” (38% and 80%, respectively, for engineers and psychologists). The “scale-side” principle was found to be very weak (2%) in this case.