It is well established that ensemble coding is regulated by physical similarity and variance in a set of stimuli. For example, observers are more accurate at judging the mean size of objects in a set if the overall size variance in the set is small. However, sometimes similarity among set members can be purely subjective. For example, faces from another race tend to look more similar than faces from one’s own race. Very little is known about whether such subjective similarity also regulates ensemble coding in the same manner as objective simil...
