Cluster Perception in the Distribution of Point Objects

Abstract

This paper aims to develop a model representing cluster perception in the distribution of point objects. Three spatial factors—that is, proximity, concentration, and density change—are considered to cause cluster perception. To measure these factors, two spatial notions based on the density of point objects are proposed: local density and relative local density. These densities are defined as the functions of a location in a map, and indicate how points are distributed around the location. Cluster perception is represented as a probabilistic function of the measures derived from the relative local density, and its likelihood is shown for model estimation. An experiment in cluster perception indicates that the model is significantly valid, and some empirical findings related to the heterogeneity of map readers in cluster perception are shown.