#DEFINE NVAR 5		! number of observed variabels
#DEFINE NFACT 1		! number of 1st order factors
#NGROUPS 1

G1: factor analysis
#include mri-iq-all-twinA-5.dat
BEGIN MATRICES ;
 P FULL NVAR NFACT free ;		! factor loadings
 D STAND NFACT NFACT fixed ;	! (no) correlations between factors
 U DIAG NVAR NVAR free ;		! subtest specific influences
 M Full 1 NVAR free ;      			! means 
END MATRICES ;

BEGIN ALGEBRA;
 C= P*D*P' +U*U' ;	! variance covariance matrix
 K=\stnd(C) ;
END ALGEBRA;

!exploratory factor analysis: if nfact = 2, one of the factor loadings has to be fixed to 0 to make it an identified model
!fix P 1 2			!

!confirmatory factor analysis: specify a verbal and performal factor
!SPECIFY P
!101 0
!102 0
!103 0
!0 204		! factor loadings on variables 4 and 5 have to be 
!0 204		! equated to make model identified

Means M /
Covariances C /

start .1 all
start 8 M 1 1 - M 1 nvar
start 1 P 1 1 - P nvar nfact
start 1 U 1 1 - U nvar nvar

OPTION RS
Option sat= 2817.131,905
END