G1 CALCULATION GROUP MZ Correlations DOC Depression -> Smoking model
Calculation NG=5
MATRICES
A SY 2 2 Free
C SY 2 2 Free
E SY 2 2 Free
B Fu 2 2
I Id 2 2 
End Matrices;

Specify B
0 0
0 0

Start .6 all
Start 0.0 A 2 1 C 2 1 E 2 1

begin algebra;
X = A*A' ;
Y = C*C' ;
Z = E*E' ;
R =      ( (I@((I-B)~))*( X+Y+Z| X+Y _
                            X+Y| X+Y+Z) * (I@((I-B)~)') ) ;
end algebra;

Option RS
End 

G2 CALCULATION GROUP DZ Correlation matrix 
Calculation
MATRICES=Group 1
H Fu 1 1 ! .5
End Matrices;

Matrix H .5

begin algebra;
X = A*A' ;
Y = C*C' ;
Z = E*E' ;
R =      ( (I@((I-B)~)) *( X+Y+Z| H@X+Y _
                           H@X+Y| X+Y+Z) * (I@((I-B)~)') ) ;
end algebra;
Option RS 
End

G3 MZ data
Data NI=4 NO=415
la S1 D1 S2 D2
km
1.0
0.24 1.00
0.81 0.24 1.00
0.24 0.49 0.24 1.00
matrices
r full 4 4 =R1 ! correlation matrix A1B1A2B2
end matrices;
cov r /
end

G4 DZ data
Data NI=4 NO=310
la S1 D1 S2 D2
km
1.0
0.45 1.00
0.54 0.30 1.00
0.30 0.23 0.45 1.00
matrices
r full 4 4 =R2 ! correlation matrix A1B1A2B2
end matrices;
cov r /
end

G5 Constrain a^2 + c^2 + e^2 =1
Constraint Ni=1
Begin Matrices = Group 1
End Matrices
Constraint \d2v(I) = \d2v(X+Y+Z) ;
End Group