** 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 ______________________________________________________________________________