Abstract
It is shown that the mean-field renormalisation group technique of Indekeu et al. (1982) may be applied directly to the self-avoiding walk (SAW) and percolation problems (without reference to the n to 0 limit of interacting spin systems). Numerical results for the SAW and bond and site percolation (both directed and undirected) problems on the square lattice, obtained by using a variety of small cells, are reported. An isotropic transformation for the percolation problems on the d-dimensional hypercubic lattice is also discussed.