!job for Falconer GxE model
!first simulate the bivariate data and then analyze the data
!next test if the genet corr is different from 1 or 0

!Simulate the data
title card: Group 1: model parameters
Data Calculation NGroups=3
Begin Matrices;
X Lower 2 2 Fixed	! genetic structure
Y Lower 2 2 Fixed	! common environmental structure
Z Lower 2 2 Fixed	! specific environmental structure
End Matrices;
Matrix X 	.50		!genetic correlation is determined by off-diagonal element
			.20 .45	!and the genetic variances of the two traits
Matrix Y 	.05
         		.05  0	! rc is 1 in this model
Matrix Z 	.45
          		0 .45	! re is 0 in this model

Begin Algebra;
A= X*X' ;	!genetic variance and covariance
C= Y*Y' ;
E= Z*Z' ;
k=\stnd(A);	! compute genetic correlation
l=\stnd(C);	! common E correlation
m=\stnd(E);	! unique E correlation
End Algebra;
End

G2: simution for MZ twin pairs
Data Calc NInput_vars=4
Matrices= Group 1
Covariances A+C+E | A+C _
           		 A+C   | A+C+E /
Options MX%E=mzsim.cov  	! write the MZ matrix to a file
Options rs					! show the MZ matrix
End

G3: simulation for DZ twin pairs
Data Calc NInput_vars=4
Matrices= Group 1
H Full 1 1
Covariances A+C+E  | H@A+C _
           		 H@A+C  | A+C+E /
Matrix H .5
Options MX%E=dzsim.cov
Options rs
End