What is a population cartogram and how does it work?

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A cartogram is a transformation of a map that uses some variable instead of land area to expand or contract the area of the original polygons based on an attribute value. Cartograms are often used for displaying population data. The Cartogram Geoprocessing tool was developed by Esri staff member Tom Gross.

What is population cartogram?

If we want to show where the world’s people are we need a population cartogram, a geographical presentation of the world where the size of the countries are not drawn according to the distribution of land, but according to the distribution of people.

How does a cartogram display population?

Take total population for example, the area cartogram to the right displays the current world population of 7.2 billion people. In this cartogram the size of a country is built using square grids, each representing 1 million people – the larger the total population, the larger the country.

What are cartograms discuss with examples?

A cartogram (also called a value-area map or an anamorphic map, the latter common among German-speakers) is a thematic map of a set of features (countries, provinces, etc.), in which their geographic size is altered to be directly proportional to a selected ratio-level variable, such as travel time, population, or GNP.

What is the purpose of cartogram?

Cartograms are used for thematic mapping. They are a particular class of map type where some aspect of the geometry of the map is modified to accommodate the problem caused by perceptually different geographies.

Why is a cartogram map useful?

1Represent a population through area cartograms

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 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 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 the advantages of a cartogram map?

Easy conversion of maps projections: Cartography makes it easy to make conversions of map projections. Maps can be maintained and updated much faster: Cartography has made it easier to maintain maps and update them much faster especially when it comes to digital maps.

What cartogram means?

Definition of cartogram
: a map showing geographically diagrammatic statistics of various kinds usually by the use of shades, curves, or dots.

Who invented cartograms?

The First Cartograms
The distinction of the first cartogram has been attributed to Émile Levasseur who produced cartograms for his economic geography related books in the 1860s and 1870s. Cartogram by Émile Levasseur published in “La France et ses Colonies“, originally published 1875.

What are the disadvantages of a cartogram map?

One of the disadvantages of the cartogram is that it inevitably changes the visual representation of geography. This has consequences as the map attempts to balance statistical accuracy, geographical accuracy and topological accuracy.

What is an area cartogram map?

Area cartogram maps are maps of non-absolute space where the areal extent is in proportion to some measured value.

What are the advantages of a cartogram?

What are the pros and cons of a cartogram map?

Advantage #2: Cartograms solve the classification/interval problem of choropleth maps because areas on the map can be distorted continuously. Disadvantage: Cartograms suffer from the same perceptual problem as proportional symbol maps, namely, that the human eye had difficulty judging the relative size of objects.