I want to compute a pseudo-$R^2$ for a model whose parameter estimation was based on maximum likelihood (function likfit()
, package geoR
, R software).
I tried to compute the $R^2$ proposed by Maddala (1983) which compares the maximized likelihood for the model without any predictor and the maximized likelihood for the model with all predictors. I got a really low value (0.01%). Did I miss something? Are there other $R^2$s which are more appropriate than the $R^2$ of Maddala?