Visual attention: Race models for selection from multielement displays

Summary A choice model for partial report from briefly exposed visual displays (Bundesen, Shibuya, & Larsen, 1985) is further investigated and related to a general class of selection models called independent race models. The choice model relates performance to the numbers of targets and distractors in the stimulus display by way of the choice axiom. In race models, the selection process is viewed as a race between items in the choice set toward a state of having been processed in that the first items reaching this state are the ones selected. If items are processed independently and processing times are exponentially distributed, selection occurs strictly in accordance with the choice axiom, so the race model is a choice model. The choice model also seems to work as a good approximation for independent race models based on other gamma distributions than the exponential one.