The Impact of Colour Difference and Colour Codability on Reference Production

It has often been observed that colour is a highly preferred attribute for use in distinguishing descriptions, that is, referring expressions with the purpose of identifying an object within a visual scene. However, most of these observations were based on visual displays containing only colours that were maximally different in hue and for which the language of experimentation possessed basic colour terms. The experiment described in this paper investigates the question whether people’s preference for colour is reduced if the colour of the target referent is similar to that of the distractors. Because colours that look similar are often also harder to distinguish linguistically, we also examine the impact of the codability of the used colour values. The results of our experiment show that, while people are indeed less likely to use colour when the colours in the display are similar, this effect is entirely due to the difficulty in naming similar colours. When the colours of target and distractors are similar but can be named using different basic colour terms, no reduction in colour use was observed.