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iaatoloye
Fluorite | Level 6

When a gamma distribution is specified in SAS, does SAS perform a log transformation to achieve and satisfy the data normality assumption? I thought using a gamma distribution violates normal assumptions. @Rick_SAS 

Thanks,

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StatDave
SAS Super FREQ

The normality assumption does not apply to a generalized linear model using a distribution other than the normal distribution. See this note.

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3 REPLIES 3
StatDave
SAS Super FREQ

The normality assumption does not apply to a generalized linear model using a distribution other than the normal distribution. See this note.

iaatoloye
Fluorite | Level 6

Thanks. I am trying to edit this statement and thinking of knocking out the second part. 

 

I would like to clarify if this is a valid statement or not: " A gamma distribution was used for all data analyses, for which a log-transformation was conducted by SAS to achieve data normality."


StatDave
SAS Super FREQ
If you fit a model using the gamma distribution for the response in the GENMOD, GLIMMIX, or other modeling procedure, then you can probably drop the phrase after the comma.

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