  In an earlier work, Damle and the author (Phys. Rev. B in press;
cond-mat/9705206) demonstrated the central role played by incoherent, inelastic
processes in transport near two-dimensional quantum critical points. This paper
extends these results to the case of a quantum transition in an anyon gas
between a fractional quantized Hall state and an insulator, induced by varying
the strength of an external periodic potential. We use the quantum field theory
for this transition introduced by Chen, Fisher and Wu (Phys. Rev. B 48, 13749
(1993)). The longitudinal and Hall conductivities at the critical point are
both $e^2/ h$ times non-trivial, fully universal functions of $\hbar \omega /
k_B T$ ($\omega$ is the measuring frequency). These functions are computed
using a combination of perturbation theory on the Kubo formula, and the
solution of a quantum Boltzmann equation for the anyonic quasiparticles and
quasiholes. The results include the values of the d.c. conductivities ($\hbar
\omega /k_B T \to 0$); earlier work had been restricted strictly to T=0, and
had therefore computed only the high frequency a.c. conductivities with $\hbar
\omega / k_B T \to \infty$.
