Proc Mixed and Residuals

[TamaraTavares]

Hello all,

I am currently running a linear mixed model using Proc Mixed for a longitudinal and clustered data set. I have two questions relating to the residuals:

(1) As each participant has two data points (longitudinal data), should I indicate (effect=participant ID) in the model line to obtain influence diagnostics for each observation for each participant?

(2) When I use the code "residual outp=lib.XXX", the residuals in the output file "XXX" are different from the ones indicated in the figures when I use the "influence". Does anyone know why these residuals are different, and importantly, which one I should use?

Thank you in advance for your help.

Best,

Tamara

[Community_Guide]

Hello @TamaraTavares,

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This prewritten response was triggered for you by fellow SAS Support Communities member @sld

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[sld]

There are lots of different kinds of residuals. You'll find details in the documentation for the MIXED procedure.

If you still have questions after reading the documentation (in particular, the RESIDUAL option in the MODEL statement), please post your code and an example of your data set.