We use an anonymized snapshot of all active Facebook users and their friendship networks to measure the intensity of connectedness between locations. Locations are assigned to users based on their information and activity on Facebook, including the stated city on their Facebook profile, and device and connection information. The Social Connectedness Index between two locations i and j is
Here, FB_Usersi and FB_Usersj are the number of Facebook users in locations i and j, and FB_Connectionsi,j is the number of Facebook friendship connections between the two.
Social Connectednessi,j, therefore, measures the relative probability of a Facebook friendship link between a given Facebook user in location i and a user in location j. Put differently, if this measure is twice as large, a Facebook user in i is about twice as likely to be connected with a given Facebook user in j.
In each dataset, we scale the measure to have a fixed maximum value (by dividing the original measure by the maximum and multiplying by 1,000,000,000) and the lowest possible value of 1. We also round the measure to the nearest integer.
You can find a more detailed methodology in the Journal of Economic Perspectives here.
Data Release – March 2020
The March 2020 datasets included are:
Countries. Each row is a country – country pair.
US Counties. Each row is a US county – US county pair.
US Zip Code Tabulation Areas. Each row is a 5-digit ZCTA – 5-digit ZCTA pair.
- GADM regions. Each row is a GADM – GADM region pair.
How to Access the Social Connectedness Index
This tool is only available to nonprofits and researchers. Interested researchers are invited to email firstname.lastname@example.org to work with the Social Connectedness Index data. If you are a researcher who is already working with the Data for Good team, feel free to connect with your standing contacts to start working with this data.