If you have ever wondered how Google collects and populates its local search results, you are not alone.
Google recently launched Google My Business, which is essentially Google’s attempt to bring Google Maps and Google+ local pages together. Businesses can use Google My Business to claim and control local listings on Google but the data that is supplied by Google My Business is only one data point.
I strongly recommend watching this video created by Moz.com featuring David Mihm who is the director of local search strategy for Moz.com.
In the video, David explains how Google gathers from multiple data source for its local search results.
In essence, the data source can largely be divided into
1) The user who actually owns the business (using Google My Business)
2) Companies that collect these data (Neustar, Acxiom etc)
3) All the websites out there
4) Government data
5) Google’s Street view data
6) Google Map Maker
What does this mean?
The diagram below shows how many data points Google can potentially use. As you can see the local search ecosystem is quite complex and not all the data collected by Google would be correct.
In fact, many businesses that have multiple locations probably suffer from duplicate listing or listings that should not exist on Google Maps.
Conclusion for how Google collects local search data
The data source that Google collects for its local search can be largely divided into 6 categories.
Since the local search ecosystem is complex and many of the data source might not be up to date, many of the listings on Google Maps could be wrong.