Influence bubbles show how correlated, or how important, a driver is to your organization's engagement score.
A big, filled in Influence bubble indicates that the driver is highly correlated with engagement at your organization, and changes for this driver will make a big difference on your Emplify score.
Small Influence bubbles indicate that the driver is not as well correlated with engagement at your organization, and changes for this driver would not make a significant difference for your Emplify score.
Influence is unique to your organization – it's like a personality test for engagement
You can think of this like a Myers-Briggs test or a Strengths Finder analysis for engagement at your organization. Influence bubbles help identify which drivers create engagement at your organization so you can focus on the factors that engage your unique workforce.
In Real Life:
If your organization mostly employs at-home caregivers, questions on the Emplify survey about Friendship might not be as applicable to engagement for your employees. They knew when they signed up for the job they were committing to working alone and never expected to be friends with their co-workers. In this case, Friendship isn't paramount (or highly correlated) to their engagement over all, so their Influence bubble is small, even though their score is low.