topic Re: Simple sales forecast procedure? in SAS Procedures

Simple sales forecast procedure?

MBI — Wed, 16 Dec 2009 14:58:57 GMT

Hi all,

I was wondering if there was a simple way to predict future sales based on past sales? I know the 'forecast' procedure exists but my version of SAS does not have the ETS license. Is there an alternative that exists in the base version?

Thanks,

MBI

Re: Simple sales forecast procedure?

DPraba79 — Wed, 16 Dec 2009 18:28:49 GMT

Try PROC ARIMA with forecast option.

Re: Simple sales forecast procedure?

MBI — Wed, 16 Dec 2009 20:27:29 GMT

DPraba79,

Thanks for the suggestion but ARIMA yeilds the following error:
ERROR: Procedure ARIMA not found.

I think it may also require the ETS license. Any other thoughts? Seems odd that there is no time series analysis in the base version of SAS when even Excel has this functionaltiy.

Thanks!

Re: Simple sales forecast procedure?

Cynthia_sas — Wed, 16 Dec 2009 22:24:14 GMT

Perhaps this paper will explain some of the the possibilities:
http://www2.sas.com/proceedings/forum2007/169-2007.pdf

I found this to be informative, about Excel and forecasting, specifically on using Excel and Trend Line Analysis:
http://www.forecastingeducation.com/tentips.htm

" Excel will readily fit a Trend Line to the series. The forecaster needs to be aware however that the Trend Line is calculated by giving equal weight to all the data-the distant past is given as much weight as the recent past. So despite that trends change over time, the Trend Line does not adapt very fast and can produce outdated forecasts. Perhaps that is why the Trend Line was the least accurate of two-dozen extrapolative procedures compared in the famous M-Competition. Excel's Trend Line is be avoided for time series forecasting. Better to replace it with Exponential Smoothing procedures."

cynthia