SEMANTIC DIFFERENTIAL AS AN INDEX OF TRAFFIC SIGN PERCEPTION AND COMPREHENSION

There is a need to develop and validate simple, inexpensive techniques for the evaluation of traffic sign messages. This paper examines the semantic differential (a paper-and-pencil test which measures psychological meaning) as a potential instrument for such evaluation. Two experiments are described, one relating semantic differential scores to comprehension and the other relating this index to glance legibility. The data indicate that semantic differential scores on all four factors (evaluative, activity, potentcy, and understandability) were highly correlated with comprehension of symbolic messages. These scores were unrelated to glance legibility of verbal messages, but two factors (evaluative and understandability) did correlate with glance legibility of symbolic messages. It was concluded that the semantic differential is a valid instrument for evaluating comprehension of symbolic sign messages and that it has advantages over other techniques.