Explicit forms are presented for the probability that a random tree in
a graph G contains any logically expressed set of edges, given that i
t contains any other logically expressed set of edges. Edge sets may b
e included or excluded, and may appear in a logical union or intersect
ion. This probability is expressed in terms of various readily calcula
ted or measured resistance values in a resistive electrical network ba
sed on G. Explicit expressions are presented for the inspectional obta
inment of resistance of the above type in a class of structures of con
siderable application, including, for example, the n-cube used in larg
e-scale computational assemblies.