  We study the 4-th Binder cumulant on $4\times{N_\sigma}^3$ lattices for a
pure SU(2) gauge theory. We use 20 data points for a sequence of ${N_\sigma}$
in $\beta$ intervals shrinking when ${N_\sigma}$ increases, in order to reduce
the nonlinear effects. Using a log-log fit of the slope versus ${N_\sigma}$, we
obtain the preliminary result $\nu=0.637(11)$ in reasonably good agreement with
the value for the 3D Ising model universality class. The corrections due to
irrelevant directions appear to be dominated by a term proportional to
${N_\sigma}^{-2.03(4)}$ which seems compatible with the breaking of rotational
symmetry.
