5  Selecting a Geography

Which geographies can I choose from? And why did you select these options?

You can use the Spatial Equity Data Tool to analyze city-level, county-level, state-level, and national level data. The original version 1 tool only included city-level analysis. County-, state-, and national-level analysis was introduced in version 2 of the tool in November 2021. We chose to add more geographies based on which ones were the most frequently requested by users. We recognize that the tool doesn’t cover all use cases, such as regional and metropolitan-area analyses, and hope to introduce additional geographic functionality in future updates.

How do I know which geography is right for my data?

We recommend determining which geography you should use depending on the geography your data cover. For example, if your dataset covers the entire US, we recommend using national-level analysis. And if your dataset covers a single county, we recommend using the county-level analysis. To figure out the geography your data cover, we recommend reading the documentation associated with your data and considering who collects the data and what their target population is.

If your dataset doesn’t fit cleanly into one of our four geographies, we recommend using a geography covered entirely by your data. For example, if your data cover a region of several states, we would recommend using the state-, county- or city-level analysis for each of the states individually. We would not recommend using national-level analysis, as your data will be compared against the entire US, so results may not be accurate.

By default, the tool will select the most frequently occurring geography in your data. So, if you uploaded regional (multistate) data and select state-level analysis, the tool will by default run the analysis for the most frequently occurring state in your data. You can manually select a different geography by using the advanced filter feature (if your dataset has a column corresponding to state) or filter your data to a specific state before uploading.

Can I use the tool for data from US territories?

We do not include the US territories in the tool, as the American Community Survey does not collect data in American Samoa, Guam, the Northern Mariana Islands, and the US Virgin Islands and does not report all of the data used in the tool for Puerto Rico. We hope in future iterations of the tool to include US territories.

What geography should I choose for data from Washington, DC?

We recommend analyzing data for Washington, DC, using city- or county-level analysis. While it is possible to analyze Washington, DC, data using state-level analysis, because the state and county boundaries for Washington, DC are equivalent, the geographic disparity map will only show a single value for Washington, DC.