What option will help the following PROC GLM to also report adjusted R-squared? thanks!
PROC GLM DATA=have ;
ABSORB year;
MODEL y = a b c /solution noint ;
RUN;
QUIT;
I do not think there is such option why do not you use PROC RSQUARE
Thank you Mohamed!
A couple of points: R squared and adjusted R squared are oddly defined with models without intercepts. Still, you could plug the R-squared value obtained from GLM into the formula for adjusted R squared (no intercept):
ADJRSQ(no int) = 1 - n * (1 - R^2)/(n - p), where n is the number of observations and p is the number of parameters fit.
Steve Denham
Thank you Steve! that's very helpful.
Steve et al.,
It was not clear to me if the model the R^2 value came from had to have any type of option in regards to the intercept or not. Do I run a normal proc glm when getting the R^2 value for the calculation. Also, do you know the name of this particular R^2 adjustment?
Thanks!
I didn't see a "-1" in the df line, so I am guessing the "noint" option needs to be used with the proc glm statement that generates the R^2, correct?
Sidenote, I get this in my Log:
"NOTE: Due to the presence of CLASS variables, an intercept is implicitly fitted. R-Square has
been corrected for the mean."
The formula I gave for the adjusted R^2 is just the standard adjustment, except that the n-1 in the numerator and denominator is replaced by n, since the intercept is not estimated. I don't remember where I found that, but Draper and Smith would be a good place to start. It needs to be the value obtained with the noint option, for it to be consistent. It is a measure of the association between the response and the X values, both considered as deviations from zero, rather than deviations from the mean.
Steve Denham
Is p the number of parameters including or excluding the intercept?
Join us for SAS Innovate April 16-19 at the Aria in Las Vegas. Bring the team and save big with our group pricing for a limited time only.
Pre-conference courses and tutorials are filling up fast and are always a sellout. Register today to reserve your seat.
Learn how use the CAT functions in SAS to join values from multiple variables into a single value.
Find more tutorials on the SAS Users YouTube channel.