In some cases, using color to represent data values just makes sense. Other times, the size of a symbol creates a clear story for the smallest and largest values. But what if you could use both of these techniques within the same map?
Smart mapping allows you to choose two attributes from your data and visualize the patterns from each attribute in a single map. One attribute is shown with color, while the other is shown with size (to show some sort of quantity).
First, choose an attribute from your data. The first attribute you choose will be shown with color.
Then, simply "Add attribute" to represent a second attribute using symbol size.
Maps use color as a representation of the values within your data. For example, color can showcase valuable patterns about time, categories, or any numeric data value.
Mapping with size, on the other hand, helps to show the quantity of something.
Combining the use of color and size can help tell a more detailed story about your data, by showcasing multiple topics at once.
This map shows unemployment as a rate (%) in the USA, by counties. The dark maroon colors tell an important story about the areas with the highest percentages of unemployment.
For reference, in October of 2016, the national unemployment rate was 4.9%.
This map clearly shows areas with above-average unemployment by using dark colors of maroon.
In this case, a color map is very useful.
Now, the map is showing the count of unemployed population over the age of 16 (working age).
This tells us a story about the quantity of people, and we see large cities (especially Los Angeles and Chicago) appear with bigger circles. These cities have a large number of unemployed people living there.
In this case, a size map is useful to show this pattern.
Now, using the color and size mapping technique, we can see both of these maps within a single map.
You can still see the areas with high unemployment rates in dark maroon, and the counties with high amounts of unemployed population with the largest circles.
This map combines two attributes, which means we can start to see possible relationships within the data.
While these are similar measurements, they each have their own meaning. Showing them together means that we can see patterns like which counties have high unemployment rates, but lower counts of unemployed population.
This map starts with Census tracts in the Chicago area, which have been geoenriched with American Community Survey (ACS) demographics. They now include information about households experiencing poverty and the education level of the people who live in these tracts.
To start mapping with color and size, click the Change Style button.
First, select an attribute.
I have chosen the percent of households with income below the poverty level, as defined by the US Census Bureau.
Smart mapping will provide me a default style based on the type of attribute I selected.
In this case, it provided me an informative choropleth map highlighting the downtown area of Chicago with higher percentages of households in poverty.
Now, select a second attribute.
I have chosen the count of adults with a high school diploma as their highest education level.
The map is now showing the first attribute with color, and the second attribute is shown using size symbols.
Within the map, you can immediately see that areas with high poverty also have high levels of population with only a high school education.
When working with the color and size technique, it is valuable to dive into the options in order to customize your map further.
Choose "Options" to work with the settings for both the color and size used in the map.
From here, you can enter the options specifically for both the color and the size settings of the map.
To start, let's look at the Counts and Amounts (Color) Options [in green].
The pane on the left now offers options for configuring the color settings of the map.
I am going to change the color ramp of this topic to red, taking into consideration some of the pointers from the How to Smart Map: Color story map.
This color change helps to provide additional emphasis about the downtown poverty levels.
I'll click OK to accept these colors.
Now, we can explore the Counts and Amounts (Size) options.
For this map, I like the way the data is represented by size, so I will keep it as-is. But keep in mind that your knowledge of a topic can add value by including your expertise on a subject.
For now, I will use a skill from 6 Easy Ways to Improve Your Maps, and add a small amount of transparency to my polygon outlines. This subtle difference will help draw attention away from the outlines, and focus the attention on the story being told by the data.
To accept all changes, click through the "OK" and "Done" options until you can see the Table of Contents again.
Now, I have a beautiful, informative map that uses both color and size to tell a valuable message.
With a configured pop-up, I can share this map with others in order to tell an important story about poverty and education levels in Chicago.
Overall, it can be broken down into two simple steps:
You're only a few clicks away from interesting and informative maps that tell multiple stories at once.
Also, if you ever find yourself wanting to switch your size and color attributes, don't worry. There's a button for that:
Mapping with both size and color opens the door to endless possibilities of maps. You'll see patterns and relationships within your datasets that you may not have found otherwise.
It is easy to try on your own datasets! Explore patterns by choosing different combinations of your attributes.
Need some inspiration? Check out the maps listed at the end of this story map, and explore their smart mapping configurations.
Also, you can visit many other smart mapping resources:
Explore the maps seen in this story map. You can even go into the smart mapping settings and see how they were created.
An error has occurred |