  We define capacity for group testing problems and deduce bounds for the
capacity of a variety of noisy models, based on the capacity of equivalent
noisy communication channels. For noiseless adaptive group testing we prove an
information-theoretic lower bound which tightens a bound of Chan et al. This
can be combined with a performance analysis of a version of Hwang's adaptive
group testing algorithm, in order to deduce the capacity of noiseless and
erasure group testing models.
