Maps and Charts

Some complex visualizations might use both maps and charts together.

Zillow home prices

Here's a look at home prices for most metropolitan statistical areas (or MSA) in the US, as published by Zillow. You can hover over or touch an MSA to get some information in it, including a time series graph.

You can explore the smaller MSAs by zooming into the map and panning around with standard device gestures. You might find that there are a couple of MSAs for which Zillow has no data.

Hierarchical Structure of the US Regions

The previous visualization combined a map together with charts that arise from tooltips. Some geographic data can be visualized using either a map or a chart. Governmental data, for example, can often be organized in a hierarchical way. The US Census Bureau, for example, divides the country up into

• Regions, then
• Divisions, then
• States,then
• Counties

and more. Here are a couple of looks at that data.

A hierarchical map

Here's the map that US Census Bureau envisions:

That map is based primarily on this PDF from the US Census. This map is interactive, though, so you can hover over it to get more information on the divisions/regions.

A collapsible tree

An alternative way to visualize hierarchical data is with a collapsible tree. The tree below, for example, shows how the whole US divides into 4 regions, each of which divides further into 2 or 3 divisions. You can click on the divisions to see what states they contains and you can click on the resulting states to reveal the counties.

Note, though, that expanding states can lead to a lot of counties! You can always click on the state, division, or region, though to recollapse.