Identification of partially occluded map symbols

Authors

  • Jari Arvi Korpi Aalto University, School of Engineering, Dept. of Real Estate, Planning and Geoinformatics
  • Mohammad Haybatollahi Aalto University, School of Engineering, Dept. of Real Estate, Planning and Geoinformatics
  • Paula Ahonen-Rainio Aalto University, School of Engineering, Dept. of Real Estate, Planning and Geoinformatics

DOI:

https://doi.org/10.14714/CP76.59

Keywords:

map symbols, symbol design, occlusion, overlapping symbols, visual variables, pictograms, map congestion

Abstract

Maps should be legible at all scales, and the information density of a map should be adapted to fulfill this goal. However, there are situations in which overlapping symbols might not be easily avoided. These kinds of cluttered or over-plotted situations often occur today in geovisual analytics and in map mash-ups created using Web 2.0 technologies. In this research project, we examine via a user test the extent to which occluded symbols can still be identifiable. Specifically, we tested how different levels of occlusion affected the accuracy and response time of finding symbols that varied in either color hue, abstract shape, or pictogram. The results of the test show that the efficiency of the symbols decreases when the symbols become partially occluded. Still, even half-occluded complex shapes can be identified quite accurately. Symbols varying in color hue seem to tolerate occlusion the best.

Author Biographies

Jari Arvi Korpi, Aalto University, School of Engineering, Dept. of Real Estate, Planning and Geoinformatics

M.Sc., Postgraduate student, Geoinformatics and Cartography

Mohammad Haybatollahi, Aalto University, School of Engineering, Dept. of Real Estate, Planning and Geoinformatics

D.Sc. Post-doctoral researcher, Statistics

Paula Ahonen-Rainio, Aalto University, School of Engineering, Dept. of Real Estate, Planning and Geoinformatics

D.Sc. (Tech), Senior University Lecturer, Geoinformatics and Cartography

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Published

2014-10-17

How to Cite

Korpi, J. A., Haybatollahi, M., & Ahonen-Rainio, P. (2014). Identification of partially occluded map symbols. Cartographic Perspectives, (76), 19–32. https://doi.org/10.14714/CP76.59

Issue

No. 76 (2013)

Section

Peer-Reviewed Articles

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