You won't be able to tell just by seeing brown leaves, have you scratched the bark on the stems and trunk yet - is there green 'life' within the core ?
You've got your answer once you've done it.

I'd wait until late spring at the earliest before giving up hope Sally. I find bay, in particular, is pretty hardy.

I wouldn't be too hopeful about the Ceanothus though - sorry. Look and see if there are any green leaves anywhere, in which case it might be all right when you do eventually cut it back. I've just taken a REALLY dead one out. It was old and straggly, so its time had come. :-(

I'd counsel you to wait - the Ceanothus, if you're lucky, may show signs of growth by May and if it does, you can cut back to wherever that is in May. Same with the Bay, really.

Thanks to everyone for their advice regarding the ceonothus
Sallybarker