Mplus VERSION 6
MUTHEN & MUTHEN
04/25/2010  10:57 PM

INPUT INSTRUCTIONS

  ! SCRIPT NAME        : ordSATut4 (cvb)
  ! GOAL                : calculation of tetrachoric correlations, check assumptions of twin
  ! DATA                : ordinal
  ! INPUT                : raw data
  ! UNI/BI/MULTI        : uni
  ! DATA-GROUPS        : MZM, DZM, MZF, DZF
  ! 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
  ! 4. as 3, plus thresholds same for males and females but correlations different for 4 gro
  ! 5. as 4, plus correlations MZM = MZF and DZM = DZF (no sex differences)
  ! 6. as 3, plus correlations MZM = MZF and DZM = DZF but thresholds differ for males and f

  data: file is ordraw1.dat;

  variable: names are id y1 y2 zygot age;
            categorical=y1 y2;
            usevar are y1 y2;
            grouping=zygot(1=MZM 2=DZM 3=MZF 4=DZF);  ! specify the groups
            missing=all(-9); ! specify missing data symbol

  model:
       [y1$1] (mzmt1);
       [y2$1] (mzmt2);
       y1 with y2 (mzmc);

  model dzm:
       [y1$1] (dzmt1);
       [y2$1] (dzmt2);
       y1 with y2 (dzmc);

  model mzf:
       [y1$1] (mzft1);
       [y2$1] (mzft2);
       y1 with y2 (mzfc);

  model dzf:
       [y1$1] (dzft1);
       [y2$1] (dzft2);
       y1 with y2 (dzfc);

  ! model test will produce Wald's test for these constraints
  model test:
       ! Uncomment to test equal thresholds for for twin 1 and twin 2
       mzmt1 = mzmt2;
       dzmt1 = dzmt2;
       mzft1 = mzft2;
       dzft1 = dzft2;

       ! Uncomment to test equal thresholds for MZ and DZ
       ! mzmt1 = dzmt1;
       ! mzft1 = dzft1;

       ! Uncomment to test equal thresholds across gender
       ! mzmt1 = mzft1;

       ! Uncomment to test no sex differences on correlation
       ! mzmc = mzfc;
       ! dzmc = dzfc;




*** WARNING
  Input line exceeded 90 characters. Some input may be truncated.
  ! 4. as 3, plus thresholds same for males and females but correlations different for 4 grou
*** WARNING
  Input line exceeded 90 characters. Some input may be truncated.
  ! 6. as 3, plus correlations MZM = MZF and DZM = DZF but thresholds differ for males and fe
*** WARNING
  Data set contains unknown or missing values for GROUPING,
  PATTERN, COHORT, CLUSTER and/or STRATIFICATION variables.
  Number of cases with unknown or missing values:  711
   3 WARNING(S) FOUND IN THE INPUT INSTRUCTIONS




SUMMARY OF ANALYSIS

Number of groups                                                 4
Number of observations
   Group MZM                                                   399
   Group DZM                                                   273
   Group MZF                                                   891
   Group DZF                                                   577

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     ZYGOT

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 MZM
     Number of missing data patterns             3

   Group DZM
     Number of missing data patterns             3

   Group MZF
     Number of missing data patterns             3

   Group DZF
     Number of missing data patterns             3


COVARIANCE COVERAGE OF DATA

Minimum covariance coverage value   0.100


     PROPORTION OF DATA PRESENT FOR MZM


           Covariance Coverage
              Y1            Y2
              ________      ________
 Y1             0.827
 Y2             0.609         0.782


     PROPORTION OF DATA PRESENT FOR DZM


           Covariance Coverage
              Y1            Y2
              ________      ________
 Y1             0.744
 Y2             0.498         0.755


     PROPORTION OF DATA PRESENT FOR MZF


           Covariance Coverage
              Y1            Y2
              ________      ________
 Y1             0.856
 Y2             0.694         0.837


     PROPORTION OF DATA PRESENT FOR DZF


           Covariance Coverage
              Y1            Y2
              ________      ________
 Y1             0.792
 Y2             0.549         0.757


UNIVARIATE PROPORTIONS AND COUNTS FOR CATEGORICAL VARIABLES

  Group MZM
    Y1
      Category 1    0.952      314.000
      Category 2    0.048       16.000
    Y2
      Category 1    0.933      291.000
      Category 2    0.067       21.000

  Group DZM
    Y1
      Category 1    0.946      192.000
      Category 2    0.054       11.000
    Y2
      Category 1    0.937      193.000
      Category 2    0.063       13.000

  Group MZF
    Y1
      Category 1    0.814      621.000
      Category 2    0.186      142.000
    Y2
      Category 1    0.822      613.000
      Category 2    0.178      133.000

  Group DZF
    Y1
      Category 1    0.838      383.000
      Category 2    0.162       74.000
    Y2
      Category 1    0.812      355.000
      Category 2    0.188       82.000


     WARNING:  THE BIVARIATE TABLE OF Y2 AND Y1 HAS AN EMPTY CELL.


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

          MZM                                0.000
          DZM                                0.000
          MZF                                0.000
          DZF                                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                            170.738
          Degrees of Freedom                     4
          P-Value                           0.0000

CFI/TLI

          CFI                                1.000
          TLI                                1.000

Wald Test of Parameter Constraints

          Value                              2.899
          Degrees of Freedom                     4
          P-Value                           0.5749

Number of Free Parameters                       12

RMSEA (Root Mean Square Error Of Approximation)

          Estimate                           0.000

WRMR (Weighted Root Mean Square Residual)

          Value                              0.015



MODEL RESULTS

                                                    Two-Tailed
                    Estimate       S.E.  Est./S.E.    P-Value

Group MZM

 Y1       WITH
    Y2                 0.650      0.137      4.729      0.000

 Thresholds
    Y1$1               1.660      0.117     14.126      0.000
    Y2$1               1.496      0.109     13.740      0.000

Group DZM

 Y1       WITH
    Y2                 0.004      0.581      0.007      0.994

 Thresholds
    Y1$1               1.606      0.145     11.109      0.000
    Y2$1               1.529      0.137     11.185      0.000

Group MZF

 Y1       WITH
    Y2                 0.649      0.055     11.801      0.000

 Thresholds
    Y1$1               0.892      0.053     16.968      0.000
    Y2$1               0.922      0.054     17.159      0.000

Group DZF

 Y1       WITH
    Y2                 0.341      0.113      3.018      0.003

 Thresholds
    Y1$1               0.987      0.070     14.039      0.000
    Y2$1               0.887      0.069     12.783      0.000


QUALITY OF NUMERICAL RESULTS

     Condition Number for the Information Matrix              0.820E-02
       (ratio of smallest to largest eigenvalue)


     Beginning Time:  22:57:39
        Ending Time:  22:57:39
       Elapsed Time:  00:00:00



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