I'm looking for someone who is familiar with the ITSM software. I have some data that needs to be fit with an ARIMA/SARIMA model and then forecast using Holt-Winters/Seasonal method. I then need to compare them using RMSE and MAPE.
I'm completely unfamiliar with ITSM and just need some help on the commands required to perform each of the above functions. The ITSM manual that comes with the download was not very helpful.
If ITSM is not your forte, is there another easily available program that would perform all of these functions for me?
HoltWinters
function is in thestats
package (auto-installed, I believe), and theastsa
package hosts thesarima
function. Compared to many statistical software manuals, documentation for R is phenomenal :) $\endgroup$