Model                                     AIC       deltaAIC        AIC wgtModel Likelihood        no.Par.     -2*LogLike
psi(.),p(.)                             30.17           0.00         0.6201         1.0000              2          26.17
psi(gully),p(.)                         31.15           0.98         0.3799         0.6126              3          25.15
