Fig 3. Examples of item difficulty for visually impaired individuals.

Examples of item difficulty are shown for 4 items (taken from the Karolinska Directed Emotional Faces database) in the gender identification task (top row) and 4 items in the emotional expression identification task (bottom row). Only the center images of the triplet are shown in every case. Listed b item measures apply to both rows and are within 0.05 d′ units of the actual b except for the right-most column where the actual b was within 0.2 d′ units of listed. Negative b item measures represent easier items.