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

INPUT INSTRUCTIONS

  ! SCRIPT NAME        : rawSAT1  (dp)
  ! GOAL                : To calculate saturated statistics & test assumptions on means and
  ! DATA                : continuous
  ! INPUT                : raw data
  ! UNI/BI/MULTI        : uni
  ! DATA-GROUPS        : MZ DZ
  ! MEANS MODEL        : grand mean mzt1, grand mean mzt2, grand mean dzt1, grand mean dzt2,
  ! VARIANCE COVARIANCE MODEL(S)        : saturated: varmzt1, varmzt2, vardzt1, vardzt2, cov
  !
  ! Evaluated models
  ! 1.Test whether grand mean t1 = grand mean t2, within zygosity (birth order effect on mea
  ! 2.Test whether grand means MZ = grand means DZ (zygosity effect on mean)
  ! 3.Test significance of sex effect
  ! 4.Test significance of age effect
  ! 5.Test whether variance twin1=variance twin2, within zygosity (birth order effect on var
  ! 6.Test whether variances MZ=DZ (zygosity effect on variance)

  data: file is example.dat;

  variable:

    ! tell Mplus what is found in the data file
    names are country famid zygos sex1 age1 height1 weight1 bmi1
                                  sex2 age2 height2 weight2 bmi2;

    ! select one phenotype per twin member, and 2 covariates per twin member
    usevar are bmi1 sex1 age1 bmi2 sex2 age2 g;

    grouping=g(1=MZ 2=DZ);  ! specify the two groups MZ and DZ

    missing=all(-1);  ! specify missing data symbol

  define:
    if (zygos==1 .or. zygos==3) then g=1 else g=2; ! defines the two groups

  model :
                 bmi1 on sex1 (b1)
                         age1 (b2);
                 bmi2 on sex2 (b1)
                         age2 (b2);

  model MZ    : [bmi1] (m11);  [bmi2] (m12);
                 bmi1  (v11);   bmi2  (v12);
  model DZ    : [bmi1] (m21);  [bmi2] (m22);
                 bmi1  (v21);   bmi2  (v22);

  model constraint:

    ! Uncomment for test 1
    ! m11=m12;
    ! m21=m22;

    ! Uncomment for test 2
    ! m11=m12;
    ! m21=m22;
    ! m21=m11;

    ! Uncomment for test 3
    ! b1=0;

    ! Uncomment for test 4
    ! b2=0;

    ! Uncomment for test 5
    ! v11=v12;
    ! v21=v22;

    ! Uncomment for test 6
    ! v11=v12;
    ! v21=v22;
    ! v21=v11;



*** WARNING
  Input line exceeded 90 characters. Some input may be truncated.
  ! MEANS MODEL	: grand mean mzt1, grand mean mzt2, grand mean dzt1, grand mean dzt2, age eff
*** WARNING
  Input line exceeded 90 characters. Some input may be truncated.
  ! VARIANCE COVARIANCE MODEL(S)	: saturated: varmzt1, varmzt2, vardzt1, vardzt2, covmz, covd
*** WARNING
  Input line exceeded 90 characters. Some input may be truncated.
  ! 1.Test whether grand mean t1 = grand mean t2, within zygosity (birth order effect on mean
*** WARNING
  Input line exceeded 90 characters. Some input may be truncated.
  ! 5.Test whether variance twin1=variance twin2, within zygosity (birth order effect on vari
*** WARNING
  Data set contains cases with missing on all variables except
  x-variables.  These cases were not included in the analysis.
  Number of cases with missing on all variables except x-variables:  3
   5 WARNING(S) FOUND IN THE INPUT INSTRUCTIONS




SUMMARY OF ANALYSIS

Number of groups                                                 2
Number of observations
   Group MZ                                                    138
   Group DZ                                                    166

Number of dependent variables                                    2
Number of independent variables                                  4
Number of continuous latent variables                            0

Observed dependent variables

  Continuous
   BMI1        BMI2

Observed independent variables
   SEX1        AGE1        SEX2        AGE2

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
Maximum number of iterations for H1                           2000
Convergence criterion for H1                             0.100D-03

Input data file(s)
  example.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
              BMI1          BMI2          SEX1          AGE1          SEX2
              ________      ________      ________      ________      ________
 BMI1           0.935
 BMI2           0.891         0.957
 SEX1           0.935         0.957         1.000
 AGE1           0.935         0.957         1.000         1.000
 SEX2           0.935         0.957         1.000         1.000         1.000
 AGE2           0.935         0.957         1.000         1.000         1.000


           Covariance Coverage
              AGE2
              ________
 AGE2           1.000


     PROPORTION OF DATA PRESENT FOR DZ


           Covariance Coverage
              BMI1          BMI2          SEX1          AGE1          SEX2
              ________      ________      ________      ________      ________
 BMI1           0.940
 BMI2           0.843         0.904
 SEX1           0.940         0.904         1.000
 AGE1           0.940         0.904         1.000         1.000
 SEX2           0.940         0.904         1.000         1.000         1.000
 AGE2           0.940         0.904         1.000         1.000         1.000


           Covariance Coverage
              AGE2
              ________
 AGE2           1.000



THE MODEL ESTIMATION TERMINATED NORMALLY



TESTS OF MODEL FIT

Chi-Square Test of Model Fit

          Value                             17.894
          Degrees of Freedom                    14
          P-Value                           0.2117

Chi-Square Contributions From Each Group

          MZ                                 7.194
          DZ                                10.700

Chi-Square Test of Model Fit for the Baseline Model

          Value                            188.497
          Degrees of Freedom                    18
          P-Value                           0.0000

CFI/TLI

          CFI                                0.977
          TLI                                0.971

Loglikelihood

          H0 Value                       -4320.631
          H1 Value                       -4311.684

Information Criteria

          Number of Free Parameters             12
          Akaike (AIC)                    8665.262
          Bayesian (BIC)                  8709.866
          Sample-Size Adjusted BIC        8671.808
            (n* = (n + 2) / 24)

RMSEA (Root Mean Square Error Of Approximation)

          Estimate                           0.043
          90 Percent C.I.                    0.000  0.094
          Probability RMSEA <= .05           0.536

SRMR (Standardized Root Mean Square Residual)

          Value                              0.066



MODEL RESULTS

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

Group MZ

 BMI1     ON
    SEX1               0.864      0.340      2.538      0.011
    AGE1               0.095      0.014      6.886      0.000

 BMI2     ON
    SEX2               0.864      0.340      2.538      0.011
    AGE2               0.095      0.014      6.886      0.000

 BMI2     WITH
    BMI1               8.574      1.267      6.766      0.000

 Intercepts
    BMI1              20.058      0.633     31.702      0.000
    BMI2              19.804      0.628     31.559      0.000

 Residual Variances
    BMI1              12.158      1.509      8.058      0.000
    BMI2              11.514      1.405      8.198      0.000

Group DZ

 BMI1     ON
    SEX1               0.864      0.340      2.538      0.011
    AGE1               0.095      0.014      6.886      0.000

 BMI2     ON
    SEX2               0.864      0.340      2.538      0.011
    AGE2               0.095      0.014      6.886      0.000

 BMI2     WITH
    BMI1               3.735      1.106      3.377      0.001

 Intercepts
    BMI1              20.640      0.629     32.836      0.000
    BMI2              20.407      0.597     34.189      0.000

 Residual Variances
    BMI1              15.905      1.800      8.835      0.000
    BMI2              11.184      1.286      8.698      0.000


QUALITY OF NUMERICAL RESULTS

     Condition Number for the Information Matrix              0.533E-04
       (ratio of smallest to largest eigenvalue)


     Beginning Time:  22:57:41
        Ending Time:  22:57:41
       Elapsed Time:  00:00:00



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