  Recently Verdu and Weissman introduced erasure entropies, which are meant to
measure the information carried by one or more symbols given all of the
remaining symbols in the realization of the random process or field. A natural
relation to Gibbs measures has also been observed. In his short note we study
this relation further, review a few earlier contributions from statistical
mechanics, and provide the formula for the erasure entropy of a Gibbs measure
in terms of the corresponding potentia. For some
  2-dimensonal Ising models, for which Verdu and Weissman suggested a numerical
procedure, we show how to obtain an exact formula for the erasure entropy. l
