st: Re: Interpretation of xtmixed repeated measures

[Janet Hill <janethill73@yahoo.co.uk>]

I am trying to learn to use xtmixed for repeated measures designs. In the example from the Repeated Measures FAQ:

anova lhist group / dog|group time time#group if dog !=6,repeated(time)
There is a significant effect of group. However when I use:
xtmixed lhist group##time if dog !=6 || dog:
margins group##time, post asbalanced
     |            Delta-method
             |     Margin   Std. Err.      z    P>|z|     [95% Conf. Interval]
-------------+----------------------------------------------------------------
       group |
          1  |  -2.093812   .3719332    -5.63   0.000    -2.822788   -1.364837
          2  |  -2.552977   .4294714    -5.94   0.000    -3.394725   -1.711228
          3  |  -.8932172   .3719332    -2.40   0.016    -1.622193   -.1642416
          4  |  -2.479522   .3719332    -6.67   0.000    -3.208498   -1.750546
             |
etc.

I can compare individual groups but I cannot see how to get an 'overall' effect as in the anova.
I would be grateful for some advice on how to achieve this or a reference to a tutorial on xtmixed and margins.

Thanks,
Janet


      

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