Hi again,
With some simpler simulated I was able to plot the effect with the proc plm using the effectplot with slicefit option.
*simulate a dataset with predictors c and x, and outcome y;
data simulation;
do i=1 to 1000;
c=int(rand('uniform',0,5));
x=int(rand('uniform',0,5));
y=rand('normal',(1/2-c)*x+x*x+2,1);
output;
end;
run;
*estimate the model and save the model to "mymodel";
proc mixed data=simulation;
model y= c*x c c*x*x;
store out=mymodel;
run;
*plot the prediction with confidence limits;
ods graphics;
ods hmtl;
proc plm restore=mymodel;
effectplot slicefit(x=x sliceby= c=2,3) /clm;
run;
Since you have many more covariates in your model, all the other covariates will be set at some level. I hope you find it usefull.
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