Mplus VERSION 7
MUTHEN & MUTHEN
09/22/2012  10:55 PM

INPUT INSTRUCTIONS

  TITLE:	this is an example of a two-group twin
  	model for  continuous outcomes using parameter
      constraints
  DATA:	FILE = ex5.21.dat;	
  VARIABLE:	NAMES = y1 y2 g;
  	GROUPING = g(1=mz 2=dz);
  MODEL:	[y1-y2]    (1);
  	y1-y2      (var);
  	y1 WITH y2 (covmz);
  MODEL dz:	y1 WITH y2 (covdz);
  MODEL CONSTRAINT:
  	NEW(a c e h);
  	var = a**2 + c**2 + e**2;
  	covmz = a**2 + c**2;
  	covdz = 0.5*a**2 + c**2;
  	h = a**2/(a**2 + c**2 + e**2);



INPUT READING TERMINATED NORMALLY



this is an example of a two-group twin
model for  continuous outcomes using parameter
constraints

SUMMARY OF ANALYSIS

Number of groups                                                 2
Number of observations
   Group MZ                                                   1000
   Group DZ                                                   1000

Number of dependent variables                                    2
Number of independent variables                                  0
Number of continuous latent variables                            0

Observed dependent variables

  Continuous
   Y1          Y2

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)
  ex5.21.dat

Input data format  FREE



THE MODEL ESTIMATION TERMINATED NORMALLY



MODEL FIT INFORMATION

Number of Free Parameters                        4

Loglikelihood

          H0 Value                       -5216.004
          H1 Value                       -5213.423

Information Criteria

          Akaike (AIC)                   10440.008
          Bayesian (BIC)                 10462.411
          Sample-Size Adjusted BIC       10449.703
            (n* = (n + 2) / 24)

Chi-Square Test of Model Fit

          Value                              5.161
          Degrees of Freedom                     6
          P-Value                           0.5233

Chi-Square Contributions 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                            995.549
          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

 Y1       WITH
    Y2                 0.753      0.028     27.122      0.000

 Means
    Y1                 0.008      0.020      0.395      0.693
    Y2                 0.008      0.020      0.395      0.693

 Variances
    Y1                 1.018      0.026     38.648      0.000
    Y2                 1.018      0.026     38.648      0.000

Group DZ

 Y1       WITH
    Y2                 0.432      0.031     13.992      0.000

 Means
    Y1                 0.008      0.020      0.395      0.693
    Y2                 0.008      0.020      0.395      0.693

 Variances
    Y1                 1.018      0.026     38.648      0.000
    Y2                 1.018      0.026     38.648      0.000

 New/Additional Parameters
    A                  0.801      0.035     23.156      0.000
    C                  0.333      0.078      4.299      0.000
    E                  0.515      0.011     45.045      0.000
    H                  0.631      0.053     11.842      0.000


QUALITY OF NUMERICAL RESULTS

     Condition Number for the Information Matrix              0.956E-04
       (ratio of smallest to largest eigenvalue)


     Beginning Time:  22:55:30
        Ending Time:  22:55:30
       Elapsed Time:  00:00:00



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