Circular cartograms via the elastic beam algorithm originated from cartographic generalization

TL;DR

This paper introduces a novel elastic beam algorithm-based method for creating circular cartograms that effectively prevent overlaps and preserve spatial relationships, improving upon existing techniques.

Contribution

The paper presents a new elastic beam displacement algorithm for circular cartogram generation that enhances quality and maintains topology better than previous methods.

Findings

Successfully generates overlap-free circular cartograms.

Maintains topological and spatial relationships effectively.

Outperforms existing approaches in quality.

Abstract

The circular cartogram, also known as the Dorling map, is a widely used tool for visualizing statistical data. It represents regions as circles with their areas in proportion to the statistical values and requires circle displacement to avoid overlap and maintain spatial relationships. In this paper, we propose a new approach for circular cartogram production that utilizes the elastic beam displacement algorithm in cartographic generalization. First, the initial circles are generated with their areas in proportion to the statistical values. Second, an elastic beam structure is built as a proximity graph based on the spatial relations between the circles. Third, the circles violating the quality requirements are considered to have a force on the nodes of a beam. Fourth, the elastic beam algorithm is applied to assign forces for each node to determine the new positions of the circles. Steps two through four are repeated until a circular cartogram that meets the defined quality requirements is obtained. The experiments indicate that the proposed approach can successfully generate circular cartograms without overlaps while maintaining topology and relative relationships with higher quality than existing approaches.