Both reports are outlined in the Jive Analytics Users Guide
Content Engagement is detailed on page 26 and Connections is covered on page 33...
This Guide is within the Documentation directory under Jive Reports.
In the Content Engagement report:
Creator = created a piece of content (Activity type = 20, Object Type = Content Type)
Consumers = viewed a piece of content (Activity type = 10, Object Type = Content Type)
The values used in the graph are variables:
Creator Engagement -> =([Creator Count]/[Active Member Count])*100
Consumer Engagement-> =([Consumer Count]/[Active Member Count])*100
In the Connections report. When a member follows another member that is classified as a connection.
Members Making Connections is a count of the number of members 'following' .
Connections Made is the Activity Count or count of connections made.
There is a work in progress definitions guide to the activity types available here: https://community.jivesoftware.com/docs/DOC-29571 It is not complete yet is what we have at this time.
I hope this helps,