! Mx ACE script for twin data
!RUN THE FULL ACE MODEL AND THEN RUN THE AE MODEL

Group1: Defines Matrices
Calc NGroups=3
	Begin Matrices;
		X Lower 1 1 free    ! genetic structure
		Y Lower 1 1 free    ! shared environment 
		Z Lower 1 1 free    ! non-shared environment
		M full 1 1 
		H Full 1 1
	End Matrices;
	Matrix H .5
	Begin Algebra;
		A= X*X';   
		C= Y*Y';   
		E= Z*Z';    
	End Algebra;
	Matrix X 0
	Matrix Y 0
	Matrix Z 1
End


Group2: MZ twin pairs
Data NInput_vars=4 NObservations=0
Labels ID zyg t1 t2
REctangular
  

End Rectangular
Select t1 t2 /
Matrices= Group 1
Covariances A + C + E  |    A + C  _
              A + C    |  A + C + E /
Means M | M /
End

Group3: DZ twin pairs
Data NInput_vars=4 NObservations=0
Labels ID zyg t1 t2
Rectangular




End Rectangular;


Select if zyg = 2 
Select t1 t2 /
Matrices= Group 1
Covariances A + C + E  |   H@A + C  _
             H@A + C   |  A + C + E /
Means M | M /
End