Principles and practice of Structural Equation Modeling Ch.7

今年4版が出て、Stataのコードもついてくる模様。

今のところraw dataはないので、共分散行列を入力してそれを分析することになる。
共分散行列は、サポートページでしめされている標準偏差と相関行列から計算することができる。
Rの場合はcor2cov()で相関行列と標準偏差を共分散行列に書き換えてくれる。
基本的にxとyの相関=(xとyの共分散)/(xの標準偏差)(yの標準偏差)なので、
相関にxとyの標準誤差をかければ、共分散は求められるので、エクセルでも計算できる。

clear all
ssd init coercive burnout support tpi experien somatic
ssd set obs 109
ssd set cov 69.009572 \ 28.868204  95.447038 \ -22.427279 -49.071453 110.695649 \   -16.805466 1.011164 9.805758 25 \  -4.987848 3.406984 2.808509 12.160924 13.822037 \  -15.269773 -0.68495 8.707448 19.179989 9.728453 27.787658
ssd list
sem (burnout<-coercive support) (tpi<-coercive support burnout) (experien<-tpi) (somatic<-tpi), cov(coercive*support)
estat gof, stats(all)
Endogenous variables

Observed:  burnout tpi experien somatic

Exogenous variables

Observed:  coercive support

Fitting target model:

Iteration 0:   log likelihood = -2052.8451  
Iteration 1:   log likelihood = -2052.8451  

Structural equation model                       Number of obs     =        109
Estimation method  = ml
Log likelihood     = -2052.8451

--------------------------------------------------------------------------------
               |                 OIM
               |      Coef.   Std. Err.      z    P>|z|     [95% Conf. Interval]
---------------+----------------------------------------------------------------
Structural     |
  burnout <-   |
      coercive |   .2935851   .0984724     2.98   0.003     .1005828    .4865873
       support |  -.3838194   .0777506    -4.94   0.000    -.5362078    -.231431
  -------------+----------------------------------------------------------------
  tpi <-       |
       burnout |   .1424866   .0510318     2.79   0.005     .0424661    .2425072
      coercive |  -.2717027   .0545622    -4.98   0.000    -.3786426   -.1647629
       support |   .0966997   .0458219     2.11   0.035     .0068904    .1865089
  -------------+----------------------------------------------------------------
  experien <-  |
           tpi |    .486437   .0538653     9.03   0.000     .3808629    .5920111
  -------------+----------------------------------------------------------------
  somatic <-   |
           tpi |   .7671996   .0692629    11.08   0.000     .6314468    .9029524
---------------+----------------------------------------------------------------
 var(e.burnout)|   67.51208    9.14499                      51.77024    88.04055
     var(e.tpi)|   19.16417   2.595923                      14.69565    24.99144
var(e.experien)|   7.833977   1.061168                      6.007324    10.21606
 var(e.somatic)|   12.95285   1.754555                      9.932622    16.89143
  var(coercive)|   68.37646   9.262076                      52.43307    89.16776
   var(support)|   109.6801   14.85695                      84.10591    143.0306
---------------+----------------------------------------------------------------
  cov(coercive,|
       support)|  -22.22152   8.563488    -2.59   0.009    -39.00565   -5.437396
--------------------------------------------------------------------------------
LR test of model vs. saturated: chi2(7)   =      3.93, Prob > chi2 = 0.7877

. estat gof, stats(all)

----------------------------------------------------------------------------
Fit statistic        |      Value   Description
---------------------+------------------------------------------------------
Likelihood ratio     |
          chi2_ms(7) |      3.931   model vs. saturated
            p > chi2 |      0.788
         chi2_bs(14) |    211.718   baseline vs. saturated
            p > chi2 |      0.000
---------------------+------------------------------------------------------
Population error     |
               RMSEA |      0.000   Root mean squared error of approximation
 90% CI, lower bound |      0.000
         upper bound |      0.078
              pclose |      0.882   Probability RMSEA <= 0.05
---------------------+------------------------------------------------------
Information criteria |
                 AIC |   4133.690   Akaike's information criterion
                 BIC |   4171.369   Bayesian information criterion
---------------------+------------------------------------------------------
Baseline comparison  |
                 CFI |      1.000   Comparative fit index
                 TLI |      1.031   Tucker-Lewis index
---------------------+------------------------------------------------------
Size of residuals    |
                SRMR |      0.034   Standardized root mean squared residual
                  CD |      0.447   Coefficient of determination
----------------------------------------------------------------------------