I assume you mean the raitings from the scoreboard?
If so, short answer, no.
Long answer, yes, but not easily. The raitings are stored using sqlite in sv.db. Editing this is not like simply editing a text file. If you know how to do sqlite queries you could modify it that way. There are a few programs available for editing sqlite databases, but it is not the most intuitive task. The raitings are also not stored in a simple raiting name = number form.
If you want to reset everyone's raitings, as well as anything else that may be stored in the sv.db file you can just delete it and let it be recreated (the server will need to be down for this).
