Subjects were presented traffic signs designed to communicate STOP, LEFT, RIGHT, and SLOW DOWN messages and asked to use their own criteria for grouping signs into groups that belong together. Probabilities of grouping according to the four intended meanings averaged 0.45, but probabilities of grouping as MERGE, KEEP, STOP, SLOW DOWN, and DO NOT ENTER averaged 0.67. These results indicate that the designer-intended priority message is comprehended by translations of the presented sign information through secondary mental operations.
Abstract