Amos does not report GFI, PGFI, AGFI and RMR when you estimate means and intercepts. This is because it is not clear how to incorporate means and intercepts into the conventional formulas for these statistics. One possibility is to calculate these statistics based on the observed variances/covariances and the fitted (implied) variances/covariances, leaving the means and intercepts out of the fit measure. That way of computing the statistics could be useful and is certainly defensible. It would make a great deal of sense in those models where means and intercepts are estimated but not constrained. On the other hand, for models that constrain means and intercepts it is important to pay attention to how well the model reproduces the means and intercepts, as well as the variances/covariances.
Another approach would be to generalize the definitions of those statistics to somehow incorporate failure to fit means and intercepts. So far, a unique, obviously correct, way of doing this has not been proposed.
For these reasons, the design decision was made not to report GFI, PGFI, AGFI and RMR when means and intercepts are estimated. |
