The Network view on the User Details page shows connections between users on your site. On the left you'll find the user you're currently investigating, and on the right, you'll find the connected users.
On the left are the features that connect the users and the number of users who share the same feature. You can create a list of users sharing one feature by clicking the drop down arrow button:
Hovering over the feature name will show you its exact value:
On the right hand side is a clickable list of the connected users. Click a username to be taken to their User Details page.
Users are displayed with their score, icons indicating whether they are Decisioned bad or not bad, and -- for un-Decisioned users -- a color (gray, yellow, or red) corresponding to how high the user's score is.
You can also batch Decision users who share the same Device ID, Cookie ID, and NormEmail Address. If users are connected by these features in your Network view, you will see the number of users:
Click on the related user's you want to Decision - and then select which Decision from the drop down.