Supporting the editing of dot maps using the spectral clustering algorithm

• Autorzy: Dziuba Natalia , Szombara Stanisław

Identyfikatory

DOI

10.2478/pcr-2025-0004

• Języki publikacji: EN

Abstrakty

EN

Automation of map production is an important subject of work of many scientists. Particular attention should be paid to dot distribution maps, the editing of which is very time-consuming and complicated due to the lack of support in GIS programs. The aim of this research was to develop a method supporting automation of dot map creation. In the study, equal-size spectral clustering algorithm was used, which was modified with a function equalizing the number of points in clusters. Spatial data on residential buildings and statistical data on the population were integrated to calculate theoretical population distributions. These data were entered into the spectral clustering algorithm based on a predefined dot value. The output clusters were then visualized in ArcGIS Pro, where manual adjustments, such as the definition of the dot size and the dispersion of overlapping markers, completed the map editing process. The results showed that the algorithm successfully created clusters representing the population distribution with an acceptable margin of error of the dot map of less than 5% for the entire county (study area – County of Pszczyna, Poland). The adaptation of the equal-size spectral clustering algorithm for cartographic purposes shows its potential to support automation of the dot distribution map editing process. The study found that reducing the input dot value slightly below the target value improved clustering precision, resulting in more consistent clusters. Despite these successes, the method has limitations, including partial reliance on manual corrections in densely populated areas where overlapping dots could not be fully automatically resolved. These issues underscore the need for further refinement to achieve full automation.

Słowa kluczowe

EN

cartography; dot map; GIS; clustering; unsupervised learning

• Wydawca: Polskie Towarzystwo Geograficzne. Oddział Kartograficzny
• Czasopismo: Polish Cartographical Review
• Rocznik: 2025
• Tom: Vol. 57, No. 1
• Strony: 58--74
• Opis fizyczny: Bibliogr. 25 poz., mapy, rys., tab., wykr.

Twórcy

autor

Dziuba Natalia

• AGH University of Krakow, Krakow, Poland

• https://orcid.org/0009-0001-0070-1988

autor

Szombara Stanisław

• AGH University of Krakow, Krakow, Poland

• https://orcid.org/0000-0002-0205-7823

Bibliografia

• Allen, J. (2022). Temporal transitions of demographic dot maps. International Journal of Cartography, 8(2), 208–222. https://doi.org/10.1080/23729333.2021.1910184
• Asche, H. (2023). Editorial aspects – In The Atlas Cookbook: Ten ingredients how to edit an atlas (pp. 20–39). ICA Commission on Atlases. https://atlas.icaci.org/wp-content/uploads/Atlas_Cookbook_2023_web.pdf
• Bërxholi, A., Doka, D., & Asche, H. (Eds.). (2003). Demographic Atlas of Albania.
• De Berg, M., Bose, P., Cheong, O., & Morin, P. (2004). On simplifying dot maps. Computational Geometry, 27(1), 43–62. https://doi.org/10.1016/j.comgeo.2003.07.005
• Distribution of rural population in 2016. (2018). In D. Rogalińska (Ed.), Atlas statystyczny Polski. Statistical Atlas of Poland (p. 25). Zakład Wydawnictw Statystycznych. https://stat.gov.pl/en/topics/other-studies/other-aggregated-studies/statistical-atlas-of-poland,17,1.html
• Fleshman, W. (2019, February 1). Spectral Clustering. Foundation and Application. Towards Data Science. https://towardsdatascience.com/spectralclustering-aba2640c0d5b
• Hey, A. (2011). Automated dot mapping - How to generate dot clusters. Proceedings of the 25th International Cartographic Conference, Paris, France, 3–8 July, CO 476.
• Hey, A., & Bill, R. (2014). Placing dots in dot maps. International Journal of Geographical Information Science, 28(12), 2417–2434. https://doi.org/10.1080/13658816.2014.928822
• Kimerling, A. J. (2013). Dotting the dot map, Revisited. Cartography and Geographic Information Science 36(2), 165–182. https://doi.org/10.1559/152304009788188754
• Rozmieszczenie ludności wiejskiej [Distribution of the rural population]. (2023). In E. Lodzińska & M. Wieczorek (Eds.), Atlas Geograficzny: Liceum i Technikum (p. 201). Demart.
• Mackay, J. R. (1949). Dotting the dot map: An analysis of dot size, number, and visual tone density. Surveying and Mapping, 9(1), 3–10.
• Martínez Barbosa, C. A. (2023a). Equal-Size Spectral Clustering. GitHub repository. https://github.com/anamabo/Equal-Size-Spectral-Clustering
• Martínez Barbosa, C. A. (2023b, February 6). Equal-size spectral clustering. A modification of this popular algorithm that builds clusters balanced in the number of points. Towards Data Science. https://towardsdatascience.com/equal-size-spectral-clustering-cce65c6f9ba3
• Pasławski, J., Lodzińska, E., & Wieczorek, W. (1993–1997). Distribution of population, 1:1500000 (ark. 62.1). In Atlas of the Republic of Poland. Główny Geodeta Kraju.
• Pasławski, J. (2015). Jak opracować mapę kropkową. Uniwersytet Warszawski.
• Pieniążek, M., & Zych, M. (2020). Statistical maps. Data visualisation methods (Vol. 1). Statistics Poland.
• Poland in numbers. (2024). Polska w liczbach. Powiat pszczyński w liczbach. https://www.polskawliczbach.pl/powiat_pszczynski
• Ratajski, L. (1989). Metodyka kartografii społeczno-gospodarczej. PPWK.
• Rozporządzenie Rady Ministrów z dnia 16 lipca 2021 r. w sprawie państwowego rejestru granic i powierzchni jednostek podziałów terytorialnych kraju Dz.U. 2021 poz. 1373 (2021a) (Polska). https://isap.sejm.gov.pl/isap.nsf/DocDetails.xsp?id=WDU20210001373
• Rozporządzenie Ministra Rozwoju, Pracy i Technologii z dnia 27 lipca 2021 r. w sprawie bazy danych obiektów topograficznych oraz bazy danych obiektów ogólnogeograficznych, a także standardowych opracowań kartograficznych Dz.U. 2021 poz. 1412 (2021b) (Polska). https://isap.sejm.gov.pl/isap.nsf/DocDetails.xsp?id=WDU20210001412
• Statistics Poland. https://stat.gov.pl/
• Suchecka, J. (2014). Statystyka przestrzenna. Metody analizy struktur przestrzennych. Wydawnictwo C.H.Beck.
• Szombara, S. (2017). Automation of dot maps production supported by BDOT10k database. Proceedings of the Baltic Geodetic Congress (BGC Geomatics), Gdansk, Poland, 22–25 June, 100–104. https://doi.org/10.1109/BGC.Geomatics.2017.34
• Tennekes, M. (2018). Tmap: Thematic maps in R. Journal of Statistical Software, 84(6), 1–39. https://doi.org/10.18637/jss.v084.i06
• Yan, H., & Weibel, R. (2008). An algorithm for point cluster generalization based on the Voronoi diagram. Computers & Geosciences, 34(8), 939–954. https://doi.org/10.1016/j.cageo.2007.07.008