A model of the perception of simple geometric figures

Presents a model of how humans perceive straight-line 2- and 3-dimensional geometric figures, e.g., triangles, trapezoids, and cubes. Major characteristics of the model are: (a) a figure is represented as a hierarchy of perceptual elements lines, angles, areas; and (b) the process of perceptually organizing a figure is portrayed as a stochastic sampling of the elements. The total number of trials to sample the elements corrected by a measure of redundancy is proposed as a measure of the figure's complexity. In experiments with 20 male and 20 female adults, the model successfully predicted the judged complexity of a wide variety of 2-dimensional figures; with some additional rationale it also predicted the perceived 3-dimensionality of figures which can be seen in either 2 or 3 dimensions, e.g., necker cubes. In general, the predictions of perceived 3-dimensionality are supported but there are discrepancies and other important unresolved problems. (26 ref.)