Hello,
I have question concerning factor analysis on variables with different
measurement levels.
The questionnaire consists of binary and ordinal variables. If I would
have just binary variables, I would use the tetrachoric correlation
coefficients. For the ordinal I assume approx. normality and then use
the ordinary factor analysis capability.
But what do I do when I have both variables? Is it an option to
construct the variance-covariance matrix by hand? And what do I take
for the correlation between binary and ordinal?
Maybe is there a model class which takes care of that, that yields
similar outcomes as factor analysis but can deal with such kind of
data (e.g. correspondence analysis).
I am grateful for every hint.
Best,
Stefan
*
* For searches and help try:
* http://www.stata.com/help.cgi?search
* http://www.stata.com/support/statalist/faq
* http://www.ats.ucla.edu/stat/stata/
