I am relatively new to stats and forecasting and was hoping to tap the wisdom of this community in regards to a question.
One of my colleagues insists that exponential smoothing presumes seasonality. I have not seen that anywhere in my investigations of the topic. To be clear, I'm looking for an actual document that states clearly "exponential smoothing assumes seasonality". I've seen reference to exponential smoothing with seasonality but that implies that there is exponential smoothing without seasonality.
So my basic question is this:
- Do all forms of exponential smoothing (simple, double and triple) assume that the underlying data are seasonal?
If the answer to the above is yes, then:
- what happens when those techniques are used on non-seasonal data?
- How strong a pattern of seasonality is required?
If the answer to the above is no, then:
- what happens when those techniques are used on seasonal data?
Several applications (such as Tableau) seem to use exponential smoothing by default when forecasting time series data. This led me to believe that seasonality cannot be a requirement of the technique, or that the requirement for seasonality is so small that it does not materially impact the forecast when there is no seasonality present. Otherwise, why use that technique as a default?
Any assistance this community can provide is most appreciated. Thank you.