Table 1.

Number of participants who showed accuracy levels of A-prime > 0.85 or A-prime < 0.15 in the pre-learning stage (24 participants in each condition).

Condition		A′ > 0.85	A′ < 0.15	High persistency
High-saliency	High-info	6/24	9/24
	Mid-info	5/24	8/24
	Total	11/48	17/48	28/48
Low-saliency	High-info	2/24	4/24
	Mid-info	0/24	3/24
	Total	2/48	7/48	9/48

These A-prime values indicate participants that were highly persistent in categorizing creatures based on the predetermined feature dimension or one of the two irrelevant feature dimensions, respectively. An A-prime score of 0.85 roughly matches d-prime (d′) = 1.5, and is at about 80% correct.