Geographic Information Systems (GIS)

Geocoding translates a text description of a location into spatial data.

An address locator is a software object that actually does the translating from text to spatial data. In order to do its job, it needs reference data. Most often, this will be in the form of street network data with address features. Think of the address locator as a street guide or map book that you use to look up an address; it directs you to the page and pinpoints the location of the address. When you enter an address you want to find, the geocoding engine converts the input address into pieces, such as number, street name, and street type, based on the parsing rules defined in the address locator. These pieces are known as address elements.

For more information on how geocoding works check out this introduction to finding places on a map.

There are several ways you can accomplish geocoding:

• ArcGIS: Using ArcGIS to geocode is not free, however Vanderbilt has a license to the software. Geocoding in this platform will use 'Credits' and may not be the best option if you are locating a lot of places. However, ArcGIS is both PHI & HIPAA approved. Here is a tutorial on how to geocode in ArcGIS.
• QGIS: QGIS is free and open-source. However, it is not necessarily PHI ready. Here is a tutorial from UC Santa Cruz on geocoding in QGIS.
• Python: To geocode in Python you can leverage a variety of libraries and packages from Google, ArcGIS, OpenStreet Map, etc. To learn more here is a tutorial with code snippets.