Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Average daily steps for users that do join the social network at time zero (treatment; red) and matched users that do not (control; blue). We observe a significant boost in activity in treatment users but no difference in control users. The effect size is practically identical with Figure 4.
