Mplus VERSION 8.8
MUTHEN & MUTHEN
04/19/2022 11:11 PM
INPUT INSTRUCTIONS
TITLE: this is an example of a two-group twin
model for continuous outcomes where
factors represent the ACE components
DATA: FILE = ex5.18.dat;
VARIABLE: NAMES = y1 y2 g;
GROUPING = g (1 = mz 2 = dz);
ANALYSIS:MODEL = NOCOVARIANCES;
MODEL: [y1-y2] (1);
y1-y2@0;
a1 BY y1* (2);
a2 BY y2* (2);
c1 BY y1* (3);
c2 BY y2* (3);
e1 BY y1* (4);
e2 BY y2* (4);
a1-e2@1;
[a1-e2@0];
a1 WITH a2@1;
c1 WITH c2@1;
MODEL dz: a1 WITH a2@.5;
INPUT READING TERMINATED NORMALLY
this is an example of a two-group twin
model for continuous outcomes where
factors represent the ACE components
SUMMARY OF ANALYSIS
Number of groups 2
Number of observations
Group MZ 1000
Group DZ 1000
Total sample size 2000
Number of dependent variables 2
Number of independent variables 0
Number of continuous latent variables 6
Observed dependent variables
Continuous
Y1 Y2
Continuous latent variables
A1 A2 C1 C2 E1 E2
Variables with special functions
Grouping variable G
Estimator ML
Information matrix OBSERVED
Maximum number of iterations 1000
Convergence criterion 0.500D-04
Maximum number of steepest descent iterations 20
Input data file(s)
ex5.18.dat
Input data format FREE
UNIVARIATE SAMPLE STATISTICS
UNIVARIATE HIGHER-ORDER MOMENT DESCRIPTIVE STATISTICS FOR MZ
Variable/ Mean/ Skewness/ Minimum/ % with Percentiles
Sample Size Variance Kurtosis Maximum Min/Max 20%/60% 40%/80% Median
Y1 0.013 -0.062 -3.543 0.10% -0.800 -0.277 -0.009
1000.000 0.992 -0.153 3.058 0.10% 0.264 0.871
Y2 0.035 -0.019 -3.045 0.10% -0.850 -0.204 0.013
1000.000 1.056 -0.174 3.125 0.10% 0.313 0.929
UNIVARIATE HIGHER-ORDER MOMENT DESCRIPTIVE STATISTICS FOR DZ
Variable/ Mean/ Skewness/ Minimum/ % with Percentiles
Sample Size Variance Kurtosis Maximum Min/Max 20%/60% 40%/80% Median
Y1 -0.017 0.052 -2.676 0.10% -0.844 -0.251 -0.026
1000.000 0.985 -0.088 3.447 0.10% 0.202 0.823
Y2 0.006 0.091 -2.754 0.10% -0.846 -0.252 -0.026
1000.000 1.042 -0.059 2.969 0.10% 0.244 0.845
THE MODEL ESTIMATION TERMINATED NORMALLY
WARNING: THE LATENT VARIABLE COVARIANCE MATRIX (PSI) IN GROUP MZ
IS NOT POSITIVE DEFINITE. THIS COULD INDICATE A NEGATIVE VARIANCE/
RESIDUAL VARIANCE FOR A LATENT VARIABLE, A CORRELATION GREATER OR EQUAL
TO ONE BETWEEN TWO LATENT VARIABLES, OR A LINEAR DEPENDENCY AMONG MORE
THAN TWO LATENT VARIABLES. CHECK THE TECH4 OUTPUT FOR MORE INFORMATION.
PROBLEM INVOLVING VARIABLE A2.
WARNING: THE LATENT VARIABLE COVARIANCE MATRIX (PSI) IN GROUP DZ
IS NOT POSITIVE DEFINITE. THIS COULD INDICATE A NEGATIVE VARIANCE/
RESIDUAL VARIANCE FOR A LATENT VARIABLE, A CORRELATION GREATER OR EQUAL
TO ONE BETWEEN TWO LATENT VARIABLES, OR A LINEAR DEPENDENCY AMONG MORE
THAN TWO LATENT VARIABLES. CHECK THE TECH4 OUTPUT FOR MORE INFORMATION.
PROBLEM INVOLVING VARIABLE C2.
MODEL FIT INFORMATION
Number of Free Parameters 4
Loglikelihood
H0 Value -5217.340
H1 Value -5214.760
Information Criteria
Akaike (AIC) 10442.679
Bayesian (BIC) 10465.083
Sample-Size Adjusted BIC 10452.375
(n* = (n + 2) / 24)
Chi-Square Test of Model Fit
Value 5.160
Degrees of Freedom 6
P-Value 0.5235
Chi-Square Contribution From Each Group
MZ 3.443
DZ 1.718
RMSEA (Root Mean Square Error Of Approximation)
Estimate 0.000
90 Percent C.I. 0.000 0.038
Probability RMSEA <= .05 0.993
CFI/TLI
CFI 1.000
TLI 1.000
Chi-Square Test of Model Fit for the Baseline Model
Value 994.489
Degrees of Freedom 2
P-Value 0.0000
SRMR (Standardized Root Mean Square Residual)
Value 0.022
MODEL RESULTS
Two-Tailed
Estimate S.E. Est./S.E. P-Value
Group MZ
A1 BY
Y1 0.801 0.035 23.136 0.000
A2 BY
Y2 0.801 0.035 23.136 0.000
C1 BY
Y1 0.333 0.078 4.293 0.000
C2 BY
Y2 0.333 0.078 4.293 0.000
E1 BY
Y1 0.515 0.011 45.047 0.000
E2 BY
Y2 0.515 0.011 45.047 0.000
A1 WITH
A2 1.000 0.000 999.000 999.000
C1 WITH
C2 1.000 0.000 999.000 999.000
Means
A1 0.000 0.000 999.000 999.000
A2 0.000 0.000 999.000 999.000
C1 0.000 0.000 999.000 999.000
C2 0.000 0.000 999.000 999.000
E1 0.000 0.000 999.000 999.000
E2 0.000 0.000 999.000 999.000
Intercepts
Y1 0.008 0.020 0.395 0.693
Y2 0.008 0.020 0.395 0.693
Variances
A1 1.000 0.000 999.000 999.000
A2 1.000 0.000 999.000 999.000
C1 1.000 0.000 999.000 999.000
C2 1.000 0.000 999.000 999.000
E1 1.000 0.000 999.000 999.000
E2 1.000 0.000 999.000 999.000
Residual Variances
Y1 0.000 0.000 999.000 999.000
Y2 0.000 0.000 999.000 999.000
Group DZ
A1 BY
Y1 0.801 0.035 23.136 0.000
A2 BY
Y2 0.801 0.035 23.136 0.000
C1 BY
Y1 0.333 0.078 4.293 0.000
C2 BY
Y2 0.333 0.078 4.293 0.000
E1 BY
Y1 0.515 0.011 45.047 0.000
E2 BY
Y2 0.515 0.011 45.047 0.000
A1 WITH
A2 0.500 0.000 999.000 999.000
C1 WITH
C2 1.000 0.000 999.000 999.000
Means
A1 0.000 0.000 999.000 999.000
A2 0.000 0.000 999.000 999.000
C1 0.000 0.000 999.000 999.000
C2 0.000 0.000 999.000 999.000
E1 0.000 0.000 999.000 999.000
E2 0.000 0.000 999.000 999.000
Intercepts
Y1 0.008 0.020 0.395 0.693
Y2 0.008 0.020 0.395 0.693
Variances
A1 1.000 0.000 999.000 999.000
A2 1.000 0.000 999.000 999.000
C1 1.000 0.000 999.000 999.000
C2 1.000 0.000 999.000 999.000
E1 1.000 0.000 999.000 999.000
E2 1.000 0.000 999.000 999.000
Residual Variances
Y1 0.000 0.000 999.000 999.000
Y2 0.000 0.000 999.000 999.000
QUALITY OF NUMERICAL RESULTS
Condition Number for the Information Matrix 0.137E-01
(ratio of smallest to largest eigenvalue)
Beginning Time: 23:11:17
Ending Time: 23:11:17
Elapsed Time: 00:00:00
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