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ACLAN
Obsidian | Level 7

Hi all, 

 

I'm running a one way ANOVA analysis in SAS based on the following code: 

 

proc anova data=dt;
class SERINDEX;
model Value0USNumdec = SERINDEX;
run;

 

The output returns:

The SAS System

The ANOVA Procedure
 
Dependent Variable: Value0USNumdec
Source DF Sum of Squares Mean Square F Value Pr > FModelErrorCorrected Total
40.002200000.0005500027.50<.0001
200.000400000.00002000  
240.00260000   

 

R-Square Coeff Var Root MSE Value0USNumdec Mean
0.8461540.9126810.0044720.490000

 

Source DF Anova SS Mean Square F Value Pr > FSERINDEX
40.002200000.0005500027.50<.0001

 

 

As an R user, I'm used to get the DF, Variance component (VC), CV (as percentage), SD and Root MSE both for the model and for the error when I perform an one-way ANOVA analysis.  

 

How can I specify this output in SAS? The user guide for Proc Anova has nothing on it. I also looked at the proc Varcomp or proc mixed procedures but they seem not to give the output I need as well. 

 

4 REPLIES 4
PaigeMiller
Diamond | Level 26

You really ought to format your output so that it is readable, that will help us and thus you get better answers and quicker answers. For output, a screen capture is fine (and readable).

 

I'm used to get the DF, Variance component (VC), CV (as percentage), SD and Root MSE both for the model and for the error

 

I do not know what the "variance component (VC)" in a one-way ANOVA means. Can you explain/provide a formula?

 

The SD**2 is the "Mean Square" column. There is no such thing as a root MSE both for the model and for the error. It only exists for the error, and is shown. The DF and CV are shown.

 

 

--
Paige Miller
ACLAN
Obsidian | Level 7

ACLAN_0-1619704740120.png

This is the R output I'm used to where the "estimates" for the errors and the model are shown. I wanted to create a similar output in SAS where, for both the error and the model I have the DF, SD and CV (%). Is there any option or another proc statement that I can use to obtained something similar to the image above?

PaigeMiller
Diamond | Level 26

I asked you to explain what VC means in a one-way ANOVA, or provide the formula, I don't see that.

 

Everything else you ask for is in the ANOVA output, or can be computed from the ANOVA output.

 

There is nothing in SAS that produces this exact output; but you can of course program something to produce this exact output (although I am skeptical that matching the R output appearance exactly is necessary, or worth the effort)

--
Paige Miller
SteveDenham
Jade | Level 19

Looking at this output, i notice a line for total, one for the one-way factor and one for the error.  The total variance is that obtained from a null model (no effects).  The error variance is the residual error after fitting the model, and the attributed variance component for the one-way factor is the difference between those two.  Now comes the tricky part to think about, and it comes from the usual definition of variance component - the variance that is attributable to some random effect.  Now if you assume that SERINDEX is a random effect (and thus that this is a simplified nested model), then that value in the R output is then a random variance component.

 

But in PROC ANOVA, SERINDEX would be fit as a fixed, non-nested effect.  Perhaps PROC NESTED would give you what you want.  Without the dataset it is hard to tell.

 

SteveDenham

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What is ANOVA?

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