ABSTRACT
Before considering the problems of estimating the parameters in structural equation models, we must consider an early development of these models due to the Swedish mathematical statistician, Karl Jöreskog (1969), which was focused on developing confirmatory factor analysis, and which turns out to be a special case of structural equation modeling. Because the common factor analysis model is likely already familiar to the reader and because it is simpler to work with than the full structural equation model, we will discuss identification in the case of a common factor model. But the principles generalize immediately to structural equation models, of which the common factor model is a special case.
