Active Admin: How to customize labels for select filter?

This seems like it should be fairly simple, buy I haven't been able to find any documentation on the subject.

I have the following filter:

filter :archived, as: :select

...which gives me a working filter in the form of a select box with options "Any", "Yes", and "No".

My question is: How do I customize these labels such that the functionality remains the same, but the labels are instead "All", "Live", and "Archived"?