Can someone please explain to me the proc means procedure when we have to use by statement.
I can understand proc means procedure when there is no by statement. as it averages acoss all variables. But i get really confused when we have 1 or more variables mentioned in by statement. I don't get if the procedure is averaging across the variables mentioned or across variables that arent mentioned.
By group processing will do all the statistics per by group - so it is as if you would feed in data sets where the values for the by group variables are constant and you then get the stats for these datasets collected in one single output (report or data set).