I am new to time series analysis. I have hourly electricity demand data for five years (having multiple seasonalities at intra-daily, intra-weekly, and annual periodicities) and I want to guess the number of AR and MA terms using ACF and PACF. Please advice me how to remove seasonalities and guess the AR and MA terms.
1 Answer
Standard ARIMA can only deal with a single seasonality, by taking seasonal differences. You might be able to work with multiple seasonal differences at different lags, but
- I have never seen this approach used by serious forecasters, which predisposes me to think it's not a good idea
- I personally think it's not a good idea, because it turns into a mess
- I don't know of any software that implements multiple-seasonal ARIMA
I'd much rather recommend you look at BATS or TBATS models, which are based on exponential smoothing. The tag wiki for the multiple-seasonalities tag contains pointers to literature. This earlier question and previous posts containing "BATS" may be useful.