How do I get a formula field to equal the result of a radio field?

I'm trying to put a formula field into a form and I want it to display the result of a single radio field in the same form (text). What would I need to put in the expression?

The reason for this is because the radio field is a status field (eg " JOB CANCELLED" and I have a subform view which cant create a "criteria view" based on the lookup of the status because it's a radio field. So I've been advised to create a formula field which equals the radio field then lookup the formula field to create my view.

Thanks