Mplus VERSION 6
MUTHEN & MUTHEN
04/25/2010 10:57 PM
INPUT INSTRUCTIONS
! SCRIPT NAME : ordSATut2 (cvb)
! GOAL : calculation of tetrachoric correlations, check assumptions of twin
! DATA : ordinal
! INPUT : raw data
! UNI/BI/MULTI : uni
! DATA-GROUPS : MZ DZ
! MEANS MODEL : n.a.
! VARIANCE COVARIANCE MODEL(S) : n.a.
! evaluated models:
! 1. no model
! 2. as 1, plus thresholds same for twin 1 and twin 2
! 3. as 2, plus thresholds same for MZ and DZ
data: file is ordraw1.dat;
variable: names are id y1 y2 zygot age;
categorical=y1 y2;
usevar are y1 y2 g;
grouping=g(1=MZ 2=DZ); ! specify the two groups MZ and DZ
missing=all(-9); ! specify missing data symbol
define: if (zygot==1 .or. zygot==3) then g=1 else g=2; ! defines the two groups
model:
[y1$1] (mzt1);
[y2$1] (mzt2);
y1 with y2 (mzc);
model dz:
[y1$1] (dzt1);
[y2$1] (dzt2);
y1 with y2 (dzc);
model test:
! Uncomment to test equal thresholds for for twin 1 and twin 2
mzt1=mzt2;
dzt1=dzt2;
! Uncomment to test equal thresholds for MZ and DZ
! mzt1=dzt1;
INPUT READING TERMINATED NORMALLY
SUMMARY OF ANALYSIS
Number of groups 2
Number of observations
Group MZ 1290
Group DZ 1561
Number of dependent variables 2
Number of independent variables 0
Number of continuous latent variables 0
Observed dependent variables
Binary and ordered categorical (ordinal)
Y1 Y2
Variables with special functions
Grouping variable G
Estimator WLSMV
Maximum number of iterations 1000
Convergence criterion 0.500D-04
Maximum number of steepest descent iterations 20
Maximum number of iterations for H1 2000
Convergence criterion for H1 0.100D-03
Parameterization DELTA
Input data file(s)
ordraw1.dat
Input data format FREE
SUMMARY OF DATA
Group MZ
Number of missing data patterns 3
Group DZ
Number of missing data patterns 3
COVARIANCE COVERAGE OF DATA
Minimum covariance coverage value 0.100
PROPORTION OF DATA PRESENT FOR MZ
Covariance Coverage
Y1 Y2
________ ________
Y1 0.847
Y2 0.667 0.820
PROPORTION OF DATA PRESENT FOR DZ
Covariance Coverage
Y1 Y2
________ ________
Y1 0.756
Y2 0.491 0.735
UNIVARIATE PROPORTIONS AND COUNTS FOR CATEGORICAL VARIABLES
Group MZ
Y1
Category 1 0.855 935.000
Category 2 0.145 158.000
Y2
Category 1 0.854 904.000
Category 2 0.146 154.000
Group DZ
Y1
Category 1 0.875 1033.000
Category 2 0.125 147.000
Y2
Category 1 0.852 977.000
Category 2 0.148 170.000
THE MODEL ESTIMATION TERMINATED NORMALLY
TESTS OF MODEL FIT
Chi-Square Test of Model Fit
Value 0.000*
Degrees of Freedom 0
P-Value 0.0000
Chi-Square Contributions From Each Group
MZ 0.000
DZ 0.000
* The chi-square value for MLM, MLMV, MLR, ULSMV, WLSM and WLSMV cannot be used
for chi-square difference testing in the regular way. MLM, MLR and WLSM
chi-square difference testing is described on the Mplus website. MLMV, WLSMV,
and ULSMV difference testing is done using the DIFFTEST option.
Chi-Square Test of Model Fit for the Baseline Model
Value 202.081
Degrees of Freedom 2
P-Value 0.0000
CFI/TLI
CFI 1.000
TLI 1.000
Wald Test of Parameter Constraints
Value 3.029
Degrees of Freedom 2
P-Value 0.2199
Number of Free Parameters 6
RMSEA (Root Mean Square Error Of Approximation)
Estimate 0.000
WRMR (Weighted Root Mean Square Residual)
Value 0.001
MODEL RESULTS
Two-Tailed
Estimate S.E. Est./S.E. P-Value
Group MZ
Y1 WITH
Y2 0.667 0.049 13.707 0.000
Thresholds
Y1$1 1.060 0.047 22.668 0.000
Y2$1 1.056 0.047 22.250 0.000
Group DZ
Y1 WITH
Y2 0.308 0.082 3.766 0.000
Thresholds
Y1$1 1.152 0.047 24.618 0.000
Y2$1 1.044 0.045 23.020 0.000
QUALITY OF NUMERICAL RESULTS
Condition Number for the Information Matrix 0.308E+00
(ratio of smallest to largest eigenvalue)
Beginning Time: 22:57:39
Ending Time: 22:57:39
Elapsed Time: 00:00:00
MUTHEN & MUTHEN
3463 Stoner Ave.
Los Angeles, CA 90066
Tel: (310) 391-9971
Fax: (310) 391-8971
Web: www.StatModel.com
Support: Support@StatModel.com
Copyright (c) 1998-2010 Muthen & Muthen
Back to the list of genetics examples