Can anyone tell me how to compute an r-squared (or equivalent) from NONMEM output. I have a covariate that markedly diminishes the objective function value (decrease by 11.5 with an associated chi-square p-value of 0.001); however, I don't know how to determine how much of the overall variability inclusion of this covariate accounts for. In a simple linear regression we get r-squared. What parameter should I look at in a NONMEM output?
Any assistency you could provide would be very much appreciated.
