Hi to all!

I am wondering whether it is possible to run a confirmatory factor analysis in SPSS using the "No of factors" choice in the Extraction dialogue box. I know all about the use of MLA as a kind of poor man's CFA in SPSS, but am wondering what people know about the "No of factors" function, what math it is based upon - essentially, whether it is a sound function to use or a waste of time.