  In this work we present the results of a numerical investigation of SU(2)
gauge theory with N_f = 3/2 flavours of fermions, corresponding to 3 Majorana
fermions, which transform in the adjoint representation of the gauge group. At
two values of the gauge coupling, the masses of bound states are considered as
a function of the fundamental fermion mass, represented by the PCAC quark mass.
The scaling of bound states masses indicates an infrared conformal behaviour of
the theory. We obtain estimates for the fixed-point value of the mass anomalous
dimension $\gamma^{\ast}$ from the scaling of masses and from the scaling of
the mode number of the Wilson-Dirac operator. The difference of the estimates
at the two gauge couplings should be due to scaling violations and lattice
spacing effects. The more reliable estimate at the smaller gauge coupling is
$\gamma^{\ast} \approx 0.38(2)$.
