Table 1.

Factorial arrangement of the four variants of NEMO fit to experimental data. In model designations, the subscripts E and H denote Exponential and Heaviside similarity-distance functions, respectively; the subscript β denotes the inclusion of an interitem similarity term.

Interstimulus similarity	Similarity-distance function
	exponential	Heaviside
yes	NEMOβE	NEMOβH
no	NEMOE	NEMOH