Assessing the affinity between two contacts allows you to know how easy it will be for them to work together.
Here's how to assess the affinity between 2 contacts, from your candidate's profile:
Click on the "Affinity" tab.
(By default, the affinity between you and the contact you are viewing appears. If you wish to evaluate the affinity between 2 of your contacts, simply select the name of the second contact from the drop-down list at the top of the affinity page).