The solitaire illusion, according to which elements of a single cluster appear more numerous than an equal number organized in several clusters, was replicated using other levels of number and different arrangements from those of Frith and Frith. An illusion of 16% was found.
References
1.
FrithC. D.FrithU.The solitaire illusion: An illusion of numerosity. Perception & Psychophysics, 1972, 11, 409–410.
2.
GinsburgN.The regular-random numerosity illusion: Rectangular patterns. Journal of General Psychology, 1980, 103, 211–216.
