I have a non-normal data. Do I need to make it normal (by appropriate transformation) prior to "Proc mixed" with "random" statement?
If you know the distribution from which the data is generated, then PROC GLIMMIX will suit your needs. Unusual links (transformations) can be handled programmatically.
If you are determined to use PROC MIXED, then the key is making the RESIDUALS normal. For instance, a bimodal distribution due to sex can never be made "normal" and the analysis does not require that the response variable be normal--only that the residuals be normally and identically distributed.
Steve Denham
Fisher's Z transform could help you to normalize it .
z=1/2* log( (1+x)/(1-x) )
Any possibilities to provide me an example of Fisher's Z transform?
Seems Fisher's Z transform is part of correlation. Will it work for single variable?
Yeah. I think it should be worked on a single variable. It is just a transform function . But I don't how good it is, You can test it.
Of course. Don't forget try to use LOG() to make the variable normal too.
Fisher's Z really only transforms values that are bounded below by -1 and above by 1 into normal deviates.
Steve Denham
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