- On 6 Aug 2004 at 10:05:00, "Kanimozhi" (kanimozhi.-at-.gvkbio.com) sent the message
Dear all,

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When we can use SAS PROC GLM and SAS PROC MIXED

PROC GLM:

When the design of the study is 2*2 3*3.

PROC MIXED:

When the design of the study is replicated.

It will be nice any one could suggest me that am I correct or not.

Thanking you,

kanimozhi.A - On 6 Aug 2004 at 10:35:27, "Bonate, Peter" (pbonate.-at-.ilexonc.com) sent the message

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Replication has nothing to do with whether to use GLM or Mixed. If the

data are complete and no missing data then either can be used, although

GLM will be faster. GLM uses an exact solution to the linear system of

equations, whereas Mixed uses an iterative process. If the data are

unbalanced and you have missing data then Mixed is the way to go because

of the way missing data are handled with GLM. GLM, I believe, deletes

the entire subject from an analysis if that person has any missing data,

but Mixed does not. You are also more restricted with GLM in that

compound symmetry is assumed. With Mixed this assumption is relaxed and

more generalized covariance matrices can be used.

Also, the BE statistical guidance used Mixed as an example, not GLM.

Hope this helps,

Pete bonate

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