** Mx startup successful **
**MX-PC 1.46b** Job started on 03/17/00 at 13:22:46
The following MX script lines were read for group 1
#NGROUPS 2
Note: #NGroup set number of groups to 2
EXAMPLE OF POWER CALCULATION FOR TWIN DATA: MZ PAIRS
DATA NINPUT=2 NOBSERVATIONS=10000 ! NB 10000 PAIRS IS JUST AN ARBITRARY NUMBER OF PAIRS
CMATRIX ! THIS IS SIMULATED COVARIANCE MATRIX: VA=0.3, EC=0.3, EW=0.4
1.000
0.600 1.000
MATRICES;
*** WARNING! ***
Input data is a correlation matrix, but CM command was used.
A DIAG 1 1 FREE
D DIAG 1 1
C DIAG 1 1 FREE
E DIAG 1 1 FREE
COVARIANCES (A+D+C+E | A+D+C_
A+D+C | A+D+C+E);
OPTIONS RSIDUALS
END
The following MX script lines were read for group 2
DZ PAIRS
DATA NINPUT=2 NOBSERVATIONS=10000
CMATRIX
1.000
0.450 1.000
MATRICES
*** WARNING! ***
Input data is a correlation matrix, but CM command was used.
A DIAG 1 1 =A1
D DIAG 1 1 =D1
C DIAG 1 1 =C1
E DIAG 1 1 =E1
G DIAG 1 1
H DIAG 1 1
COVARIANCES (A+D+C+E | G@A+H@D+C_
G@A+H@D+C | A+D+C+E) ;
MATRIX G 0.5
MATRIX H 0.25
START .25 ALL
OPTIONS RSIDUALS MULTIPLE
END
PARAMETER SPECIFICATIONS
GROUP NUMBER: 1
Example of power calculation for twin data: MZ pairs
MATRIX A
This is a DIAGONAL matrix of order 1 by 1
1
1 1
MATRIX C
This is a DIAGONAL matrix of order 1 by 1
1
1 2
MATRIX D
This is a DIAGONAL matrix of order 1 by 1
It has no free parameters specified
MATRIX E
This is a DIAGONAL matrix of order 1 by 1
1
1 3
GROUP NUMBER: 2
DZ PAIRS
MATRIX A
This is a DIAGONAL matrix of order 1 by 1
1
1 1
MATRIX C
This is a DIAGONAL matrix of order 1 by 1
1
1 2
MATRIX D
This is a DIAGONAL matrix of order 1 by 1
It has no free parameters specified
MATRIX E
This is a DIAGONAL matrix of order 1 by 1
1
1 3
MATRIX G
This is a DIAGONAL matrix of order 1 by 1
It has no free parameters specified
MATRIX H
This is a DIAGONAL matrix of order 1 by 1
It has no free parameters specified
MX PARAMETER ESTIMATES
GROUP NUMBER: 1
Example of power calculation for twin data: MZ pairs
MATRIX A
This is a DIAGONAL matrix of order 1 by 1
1
1 0.3000
MATRIX C
This is a DIAGONAL matrix of order 1 by 1
1
1 0.3000
MATRIX D
This is a DIAGONAL matrix of order 1 by 1
1
1 0.0000
MATRIX E
This is a DIAGONAL matrix of order 1 by 1
1
1 0.4000
OBSERVED COVARIANCE MATRIX
1 2
1 1.0000
2 0.6000 1.0000
EXPECTED COVARIANCE MATRIX
1 2
1 1.0000
2 0.6000 1.0000
RESIDUAL MATRIX
1 2
1 -1.6160E-08
2 -1.7294E-08 -1.6160E-08
Function value of this group: 3.7792E-12
Where the fit function is Maximum Likelihood
GROUP NUMBER: 2
DZ PAIRS
MATRIX A
This is a DIAGONAL matrix of order 1 by 1
1
1 0.3000
MATRIX C
This is a DIAGONAL matrix of order 1 by 1
1
1 0.3000
MATRIX D
This is a DIAGONAL matrix of order 1 by 1
1
1 0.0000
MATRIX E
This is a DIAGONAL matrix of order 1 by 1
1
1 0.4000
MATRIX G
This is a DIAGONAL matrix of order 1 by 1
1
1 0.5000
MATRIX H
This is a DIAGONAL matrix of order 1 by 1
1
1 0.2500
OBSERVED COVARIANCE MATRIX
1 2
1 1.0000
2 0.4500 1.0000
EXPECTED COVARIANCE MATRIX
1 2
1 1.0000
2 0.4500 1.0000
RESIDUAL MATRIX
1 2
1 -1.6160E-08
2 3.3245E-09 -1.6160E-08
Function value of this group: 4.4448E-12
Where the fit function is Maximum Likelihood
Your model has 3 estimated parameters and 6 Observed statistics
Chi-squared fit of model >>>>>>> 0.000
Degrees of freedom >>>>>>>>>>>>> 3
Probability >>>>>>>>>>>>>>>>>>>> 1.000
Akaike's Information Criterion > -6.000
RMSEA >>>>>>>>>>>>>>>>>>>>>>>>>> 0.000
This problem used 0.7% of my workspace
Task Time elapsed (DD:HH:MM:SS)
Reading script & data 0: 0: 0: 0.05
Execution 0: 0: 0: 0.06
TOTAL 0: 0: 0: 0.11
Total number of warnings issued: 2
______________________________________________________________________________
! Now calculate expected chi-square and power associated with VA
Multiple fit option in effect.
The following MX script lines have been read:
DROP 1
OPTIONS POWER=0.05,1 ! SIGNIFICANCE LEVEL, DF
END
PARAMETER SPECIFICATIONS
GROUP NUMBER: 1
Example of power calculation for twin data: MZ pairs
MATRIX A
This is a DIAGONAL matrix of order 1 by 1
It has no free parameters specified
MATRIX C
This is a DIAGONAL matrix of order 1 by 1
1
1 2
MATRIX D
This is a DIAGONAL matrix of order 1 by 1
It has no free parameters specified
MATRIX E
This is a DIAGONAL matrix of order 1 by 1
1
1 3
GROUP NUMBER: 2
DZ PAIRS
MATRIX A
This is a DIAGONAL matrix of order 1 by 1
It has no free parameters specified
MATRIX C
This is a DIAGONAL matrix of order 1 by 1
1
1 2
MATRIX D
This is a DIAGONAL matrix of order 1 by 1
It has no free parameters specified
MATRIX E
This is a DIAGONAL matrix of order 1 by 1
1
1 3
MATRIX G
This is a DIAGONAL matrix of order 1 by 1
It has no free parameters specified
MATRIX H
This is a DIAGONAL matrix of order 1 by 1
It has no free parameters specified
MX PARAMETER ESTIMATES
GROUP NUMBER: 1
Example of power calculation for twin data: MZ pairs
MATRIX A
This is a DIAGONAL matrix of order 1 by 1
1
1 0.0000
MATRIX C
This is a DIAGONAL matrix of order 1 by 1
1
1 0.5250
MATRIX D
This is a DIAGONAL matrix of order 1 by 1
1
1 0.0000
MATRIX E
This is a DIAGONAL matrix of order 1 by 1
1
1 0.4750
OBSERVED COVARIANCE MATRIX
1 2
1 1.0000
2 0.6000 1.0000
EXPECTED COVARIANCE MATRIX
1 2
1 1.0000
2 0.5250 1.0000
RESIDUAL MATRIX
1 2
1 -1.5065E-08
2 7.5000E-02 -1.5065E-08
Function value of this group: 151.2512
Where the fit function is Maximum Likelihood
GROUP NUMBER: 2
DZ PAIRS
MATRIX A
This is a DIAGONAL matrix of order 1 by 1
1
1 0.0000
MATRIX C
This is a DIAGONAL matrix of order 1 by 1
1
1 0.5250
MATRIX D
This is a DIAGONAL matrix of order 1 by 1
1
1 0.0000
MATRIX E
This is a DIAGONAL matrix of order 1 by 1
1
1 0.4750
MATRIX G
This is a DIAGONAL matrix of order 1 by 1
1
1 0.5000
MATRIX H
This is a DIAGONAL matrix of order 1 by 1
1
1 0.2500
OBSERVED COVARIANCE MATRIX
1 2
1 1.0000
2 0.4500 1.0000
EXPECTED COVARIANCE MATRIX
1 2
1 1.0000
2 0.5250 1.0000
RESIDUAL MATRIX
1 2
1 -1.5065E-08
2 -7.5000E-02 -1.5065E-08
Function value of this group: 125.4053
Where the fit function is Maximum Likelihood
Your model has 2 estimated parameters and 6 Observed statistics
Chi-squared fit of model >>>>>>> 276.657
Degrees of freedom >>>>>>>>>>>>> 4
Probability >>>>>>>>>>>>>>>>>>>> 0.000
Akaike's Information Criterion > 268.657
RMSEA >>>>>>>>>>>>>>>>>>>>>>>>>> 0.082
Power of this test, at the 0.0500 significance level
with 1. df is 1.000000
Based on your combined observed sample size of 20000.
The following sample sizes would be required to reject the hypothesis:
Power Total N
.25 119.
.50 278.
.75 502.
.80 567.
.90 760.
.95 939.
.99 1328.
This problem used 0.7% of my workspace
Task Time elapsed (DD:HH:MM:SS)
Reading script & data 0: 0: 0: 0.00
Execution 0: 0: 0: 1.54
TOTAL 0: 0: 0: 1.54
Total number of warnings issued: 2
______________________________________________________________________________