A cartogram is a map in which area is not preserved. Instead, another thematic mapping variable like travel time or Gross National Product is substituted for land area. In other words, the geometry or space of the map is distorted in order to convey the information of this alternate variable. There are two main types of cartograms: area and distance cartograms. Presidential popular votes cartogram, in which the sizes of counties have been rescaled according to their population. ... Presidential popular votes cartogram, in which the sizes of counties have been rescaled according to their population. ... United States of America, showing states, divided into counties. ... Presidential election results map. ... For other uses, see Map (disambiguation). ... The Mercator projection shows courses of constant bearing as straight lines. ... Measures of national income and output are used in economics to estimate the value of goods and services produced in an economy. ...
An area cartogram is sometimes referred to as value-by-area map or an isodemographic map. The latter particularly for a population cartogram, which illustrates the relative sizes of the populations of the countries of the world by scaling the area of each country in proportion to its population; the shape and relative location of each country is retained to as large an extent as possible, but inevitably a large amount of distortion results. Other synonyms in use are anamorphic map or density-equalizing map[1][2]. The German word for cartogram is Kartenanamorphote, and not Kartogramm [3] This is an alphabetical list of the sovereign states of the world, including both de jure and de facto independent states. ...
A distance cartogram may also be called a central-point cartogram. This form is typically used to show relative travel times and directions from vertices in a network.
Bibliography
Campbell, John. Map Use and Analysis. New York: McGraw-Hill, 2001.
Gillard, Quentin. "Places in the News: The Use of Cartograms in Introductory Geography Courses." Journal of Geography. 78 (1979): 114-115.
Tobler, Waldo. "Thirty-Five Years of Computer Cartograms." Annals of the Association of American Geographers. 94 (2004): 58-73.
Vescovo, Victor. "The Atlas of World Statistics." Dallas: Caladan Press, 2005.
The two-variable contiguous area cartogram on the left depicts enumeration units proportionally scaled to the data that they represent.
The cartogram is therefore one of the truest form of quantitative mapping.
This is why a cartogram legend should include a continuous tone color bar, showing a continuous data range from minimum to maximum value (not labeled).
A cartogram is a type of graphic that depicts attributes of geographic objects as the object's area.
Because a cartogram does not depict geographic space, but rather changes the size of objects depending on a certain attribute, a cartogram is not a true map.
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.
Feeds |
Contact