Cartography is the art and science of creating and designing maps. When I started my graduate career, I naively assumed that maps were a kind of raw data, something that is simply not true! I had a lot to learn--Maps are interpreted data. They are models of reality that require decisions on the part of the cartographer on how to simplify (cartographic generalization) highlight, and represent geographic data. In making the decisions, the cartographer creates a visual hierarchy, that is, she determines how features are displayed on a map to emphasize or de-emphasize aspects of the data that are displayed.
Map Design Elements
Scale bar: a graphical device used to represent map scale
North arrow: is a graphical device on a map used to show the orientation of the map
Legend: graphical device found on a map that explains the meaning of symbols and colors found on a map.
Type: The lettering used on a map used to label and identify features
Types of Maps
There are different categories of maps.
A reference map is a map that serves to show the location of features, examples include zoning maps, topographic maps, and street maps.
A thematic map is designed to convey information pertaining to a specific theme or feature.
A cholopleth map is a kind of thematic map where data is displayed in discrete categories.
A base map is used in ESRI Products (AGO, ArcMap, ArcPro) as background context for the data you will be working with and visualizing.
Data Display on Maps
Data classification can be obtained using different mathematical operations, and each will display different results. Often prior to doing data classification it may be desirable to normalize the data. Normalized data is altered so that the data values are comparable- using % data is one way to normalize data- it makes sense often to compare percentages instead of regular count values.
Natural breaks is a data classification method that selects class break levels by searching for spaces in the data values.
Quantile is a data classification method that attempts to place an equal number of data values in each class.
Equal intervals is a data classification method that selects class break levels by taking the total span of values and dividing by the number of desired classes
Standard deviation is a data classification method that computes class break values by using the mean of the data values and the average distance a value is away from the mean.
Here is a site that may be helpful.
http://individual.utoronto.ca/lackner/ggr272/DataClassificationMethods.pdf
The map design process contains many steps. Identifying the audience and purpose are important.
Open up the link below and compare the two maps. Which one has a better layout? How come?
