Variable Transformation

[ash3]

I have 50 continuous variables and I want to check normality condition of each variable. Is there any syntax available  which suggest me automatically best transformation (whether it is  log, exp or sqrt)  of each variable in one go.

[ballardw]

I would start with Proc univariate as you can request a test for normality as well as get some descriptive statistics and/or plots of distributions that would give a hint which transform might be useful for those that aren't normal, or close enough for your purpose.

Proc univariate data=have normal;

   var <list your variable here or use on of the SAS variable list forms>;

run;

would get you started. Histogram or CDFPLOT or other of the plot statements might be helpful.

[haoduonge]

Hi all,

I want to continue with this question.

In STATA we have qladder to check that, I hope SAS has something similar by now too.

Hao

[PaigeMiller]

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@haoduonge wrote:

Hi all,

I want to continue with this question.

In STATA we have qladder to check that, I hope SAS has something similar by now too.

Hao

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we don't know what qladder does, please explain

Also, what is wrong with doing what @ballardw said above? Seems to be a rather complete answer to the original question.

[haoduonge]

I meant the code that can be used to exam multiple variables silmultaneously (avoid to run over and over again).

Thanks!

Hao

[Ksharp]

1) Try Box-Cox transformation, @Rick_SAS wrote a blog about this:
https://blogs.sas.com/content/iml/2022/08/22/box-cox-transform.html
https://blogs.sas.com/content/iml/2022/08/17/box-cox-regression.html

2) Check PROC GENMOD 's ASSESS Statement