Module 11 - Cartography - Dot Mapping

Dot Map showing Urban Population Distribution
in South Florida

This type of map is a dot map of the population distribution of urban South Florida.  All of the dots are the same size and each represents a given value, in this case, 20,000 persons. The source of the population data is the US Census Bureau, and it has been added to ArcMap, by county, in the form of an Excel spreadsheet.

The dot symbols are more tightly packed in areas where population density is higher, providing a very intuitive presentation.  In this map, the dots representing the population of each county have also been restrained to areas defined as urban.  To do this, the ArcMap masking tool is used within the symbology controls of the population layer.  As a natural result of this masking operation, no dots fall within areas of water, because no urban areas are located there.