Scientific- Research Quarterly of Geographical Data (SEPEHR)

Scientific- Research Quarterly of Geographical Data (SEPEHR)

A Study of Methods for Data Classification in Choropleth Maps (Case Study: Preparation of Population Concentration Map of Iran)

Document Type : Research Paper

Authors
Mehran Maghsudi 1
Sepideh Zandieh 2
1 Assistant Professor, Faculty of Geography, University of Tehran
2 Expert, National Cartographic Center of Iran
Abstract
Today, almost all reports, scholarly research and applied projects that somehow deal with the dispersion of geographic phenomena use thematic maps.
In the European countries production of thematic maps go back to the 17th century, but in our country, the preparation of these maps began with the compilation of atlases by some organizations in the 1960s. A special type of thematic maps which has been widely used, is the choropleth map. Choropleth maps are used to display the distribution of quantitative phenomena over a political or administrative area such as province, city, district and rural districts.
Choropleth maps are usually represented by graduated color or hachures. An important point in the development of choropleth maps is to find the appropriate classification system for the data utilized. In fact, there are various classification systems in this regard that may be confused by users if a proper classification system is not selected for information display.
In this research, we tried to study the classification methods in choropleth maps and specify the characteristics of each of them.
Keywords
cartography
Thematic Map
Choropleth
Classification
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