Chartograms

A chartogram, also known as a cartogram or a value-by-area map, is a data visualization that transforms geographic space to represent the size of a particular variable. Instead of using geographic area to depict size, chartograms distort the shapes and sizes of countries, states, or regions based on the magnitude of a chosen metric. For example, a world population cartogram would show countries with larger populations appearing proportionally larger on the map, regardless of their actual landmass.

This distortion allows for a more intuitive understanding of how different entities contribute to a total. Areas with high values swell, while those with low values shrink. This method can be particularly effective for comparing contributions to a global or national total, such as economic output, population density, or election results.

The creation of chartograms involves algorithms that recalculate the size of each region based on its data value. This process can lead to unusual shapes and juxtapositions, as traditional geographical relationships are sacrificed for data representation. Despite their altered appearance, chartograms excel at highlighting disparities and relative importance that might be overlooked on a standard map. They are a powerful tool for revealing patterns and insights by prioritizing data over strict geographical accuracy.