Horn's parallel analysis on polychoric correlation matrix (with factor analysis)

[Rashad Jafarov]

Dear All,

I am trying to perform Horn's parallel analysis on polychoric correlation matrix for principal components factor analysis. User written command paran (help file here: http://fmwww.bc.edu/RePEc/bocode/p/paran.html) seemingly allows for performing the parallel analysis not only on items (variables) but also on a matrix, which I have attemtpted to do but have run into the following error code in STATA:

paran mat(R), n($N) factor(pcf)
factor variables and time-series operators not allowed
r(101);

end of do-file

I have done the following;

***Performed polychoric correlation on my set of variables***

polychoric $pcflist0

*** Stored the number of obs to N***

global N = r(sum_w)

****Saved the output matrix of polychoric command to R***

matrix R = r(R)

***Finally, parallel analysis on this saved matrix***

paran mat(R), n($N) factor(pcf)

However as I mentioned eralier, at the end I receive the following STATA error;

paran mat(R), n($N) factor(pcf)
factor variables and time-series operators not allowed
r(101);

end of do-file

What am I missing here?

Kind regards,

Rashad Jafarov
Msc.Behavioral Economics
Erasmus School of Economics