Attn: math buffs, probability?
There are times when a stud finder won't work to find studs in a ceiling or wall, and you have to drill in exploratory fashion to find them. Assume that you know the orientation of the studs so we can work in one dimension. If I drill and hit a stud (w = 1.5" in width) where should I drill the next hole (obviously between -w and +w) to learn the maximum amount of information about where it is centered?