Hello,

I have used the SEM builder to specify a Bi-factor model in Stata with two latent factors - one factor has three indicators and the other factor has four indicators and a general factor where all the indicators of the two factors map onto the general factor. The results returned = not concave. This suggests that the model is unidentified, (am I correct?)

I have two additional questions:

1) Can I successfully run a bifactor model in Stata and can anyone point me to some general information which will allow me to locate specific goodness of fit indices and factor rotation relevant to Stata?

2) Any ideas on why the model does not run? (and perhaps provide some supporting information to help clarify the problem.

Many thanks in advance for any responses.
Gill