## What is a Dorling cartogram?

A Dorling cartogram is a non-contiguous area cartogram, where numerical (quantitative) data using either a ratio or interval scale is displayed for individual geographical features or locations using the areas of circles placed in locations roughly corresponding to actual geographical regions.

## What are the different types of cartograms?

There are four main types of cartogram which each represent the mapped variable differently – non-contiguous, contiguous, graphical and gridded.

What is a cartogram and why is it useful for demographers?

Cartograms are maps in which areas of geographic regions, such as countries and states, appear in proportion to some variable of interest, such as population or income. They are popular visualizations for geo-referenced data that have been used for over a century [50].

What does a population cartogram depict?

An area cartogram is a map that alters an entire physical location by scaling a chosen economic, social, political, or environmental factor. Take total population for example, the area cartogram to the right displays the current world population of 7.2 billion people.

### What are the three types of cartograms?

There are three main types of cartograms, each have a very different way of showing attributes of geographic objects- Non-contiguous, Contiguous and Dorling cartograms.

### What are non-contiguous cartograms?

Non-contiguous cartograms are a type of area cartogram. In a non-contiguous cartogram, the features are not connected and enlarge or shrink based on a quantified value.

Why are cartograms useful?

Cartograms are particularly useful as population cartograms, which can illustrate the relative sizes of the populations of the countries of the world by scaling the area of each country in proportion to its population.

What is the difference between a cartogram and Choropleth?

Choropleth maps show us how much geographic area is affected. On some maps, this means that large regions where only a few people take up a lot of space on the screen. Population cartograms, on the other hand, drive more attention to populated areas.

## Is a cartogram map a thematic map?

A cartogram is a thematic map type in which the size of an area is rescaled to be proportional to the feature it represents.

## How are the two cartograms different?

Cartograms vary on their degree in which geographic space is changed; some appear very similar to a map, however some look nothing like a map at all. There are three main types of cartograms, each have a very different way of showing attributes of geographic objects- Non-contiguous, Contiguous and Dorling cartograms.

When should you not use a cartogram?

Do not use cartograms when balancing statistical accuracy, geographical accuracy and topological accuracy are of importance to you. 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.

What is Chorochromatic technique?

Basically, the chorochromatic technique implies the drawing of bounding lines to delimit specific areas within which shading or coloring is applied to mark distinctive features [2]. Chorochromatic maps can be simple or compound.