Choropleth map

A choropleth map that visualizes the fraction of Australians that identified as Anglican at the 2011 census. The selected districts are local government areas, the variable is spatially intensive (a proportion) which is unclassed, and a part-spectral sequential color scheme is used.

A choropleth map (from Ancient Greek χῶρος (khôros) 'area, region' and πλῆθος (plêthos) 'multitude') is a type of statistical thematic map that uses pseudocolor, meaning color corresponding with an aggregate summary of a geographic characteristic within spatial enumeration units, such as population density or per-capita income.[1][2][3]

Choropleth maps provide an easy way to visualize how a variable varies across a geographic area or show the level of variability within a region. A heat map or isarithmic map is similar but uses regions drawn according to the pattern of the variable, rather than the a priori geographic areas of choropleth maps. The choropleth is likely the most common type of thematic map because published statistical data (from government or other sources) is generally aggregated into well-known geographic units, such as countries, states, provinces, and counties, and thus they are relatively easy to create using GIS, spreadsheets, or other software tools.

  1. ^ Dent, Borden D.; Torguson, Jeffrey S.; Hodler, Thomas W. (2009). Cartography: Thematic Map Design (6th ed.). McGraw-Hill.
  2. ^ Tobler, Waldo (1973). "Choropleth Maps Without Class Intervals?". Geographical Analysis. 5 (3): 262–265. Bibcode:1973GeoAn...5..262T. doi:10.1111/j.1538-4632.1973.tb01012.x.
  3. ^ Adams, Aaron; Chen, Xiang; Li, Weidong; Zhang, Chuanrong (2020). "The disguised pandemic: the importance of data normalization in COVID-19 web mapping". Public Health. 183: 36–37. doi:10.1016/j.puhe.2020.04.034. PMC 7203028. PMID 32416476.