They are primarily used to display emphasis and for analysis as nomographs. Cartograms leverage the fact that size is the most intuitive visual variable for representing a total amount.

When should you not use a cartogram?

When Not to Use a Cartogram

Maps depend on variation in scale to represent a large area and a cartogram is not a true representation of the real-world area and may give incomplete information. One of the disadvantages of the cartogram is that it inevitably changes the visual representation of geography.

What is the use of dot map?

Definition. Dot maps are used to visualise distributions and densities of a big number of discrete distributed single objects whereas, in contrast to location maps, not every single object is depicted but one symbol represents a constant number of objects.