Consequently, the approach of Madden and Stynes leads to a discrete solution which is nodally
exact except in a small neighbourhood of the corner (1, 0).
Critically, however, any transformation effect observed with the B-C relation could be explained by the facts that (i) B had already been reinforced as the correct discrimination when the B-C pair appeared in the presence of the happier-than contextual cue, and (ii) B was nodally
adjacent to A, the selection of which was always reinforced.
Most participants showed the emergence of symmetrical relations between the unitary samples and the trained comparisons (C-AB), and all showed the emergence of transitive relations between the unitary sample stimuli and the nodally
linked comparison (AB-D).
For instance, subjects chose the nonsense syllable that was nodally
farthest from the nonsense syllable sample when the trial was presented with the shape that occasioned reinforcement for the choice of a comparison line that differed maximally in length from a sample line.