03-14-2013 01:56 PM
We don't yet have SAS/GRAPH and are considering purchasing. Can you describe the process (short version) to add vertical error bars around a series of points? These will be confidence intervals around the mean. Would this be GPLOT or GCHART or other? Anything else we should know? Thanks
03-14-2013 02:06 PM
Both will do it for you.
proc gchart data = sashelp.class;
vbar sex/ type=MEAN errorbar=BOTH clm=95 sumvar=age;
And here is more info:
For proc gplot you will have to calculate yourself the mean +/- s.e. to get the upper/lower Confidence Limits.Then use an overlay to plot.
Here is more information:
03-14-2013 03:31 PM
You can also use PROC SGPLOT. For bar charts, line charts, and dot plots, you can have the procedure compute three types of limits: clm, stderr, and stddev. YOu can also specify a multiplier for stderr and stddev.
proc sgplot data=sashelp.class;
vbar age / response=weight stat=mean limitstat=clm;
For plots, you can use overlays to plot the limit bars:
proc sgplot data=somedata;
series x=xvar y=yvar;
scatter x=xvar y=yvar / yerrorupper=ulimitvar yerrorlower=llimitvar;
The SG procedure were introduced in SAS 9.2 as part of SAS/GRAPH; however, as of SAS 9.3, they are part of BASE SAS.
Hope this helps!