# SAS code for converting arcsine-transformed percent data to original unit

#### sb1605

##### New Member
I am working on the SAS code for multiple linear regression where the dependent variable is a continuos variable and is in percent. I log transformed this dependent variable using the SAS code below for due to heteroscedasticity issues

data a; set X;
y=wtloss_serv;
ny=arsin(sqrt(y/100));
run;

Now I am trying to convert the transformed data back to its original units. But I am not really sure about the SAS code to be used for this back transformation.

Would really appreciate any help with the code.

#### Con-Tester

##### Member
I don’t see any log transform in your code, only an arcsine-square root transformation, but if I understand you correctly, you want to calculate y (and wtloss_serv) when you have ny.

The code for doing this would be:
Code:
y = 100*sin(ny)*sin(ny);
wtloss_serv = y;
(There are other ways that all boil down to the same thing.)

#### sb1605

##### New Member
I don’t see any log transform in your code, only an arcsine-square root transformation, but if I understand you correctly, you want to calculate y (and wtloss_serv) when you have ny.

The code for doing this would be:
Code:
y = 100*sin(ny)*sin(ny);
wtloss_serv = y;
(There are other ways that all boil down to the same thing.)

My bad, I meant arcsine square root transformation not log transformation. Thank you so much for the code. This was very helpful.