Exponential smoothing model

[Oliss4t]

Is ist addative or multuplicative? Needs to be decided based on the seasonality. If the variation of the seasonality is constant, then additive, otherwise multuplicative

[conorfallon1995]

I think it is multiplicative:

'The additive decomposition is the most appropriate if the magnitude of the seasonal fluctuations, or the variation around the trend-cycle, does not vary with the level of the time series. When the variation in the seasonal pattern, or the variation around the trend-cycle, appears to be proportional to the level of the time series, then a multiplicative decomposition is more appropriate. Multiplicative decompositions are common with economic time series.'

Source: https://otexts.com/fpp2/components.html

Can ask her on Wednesday as well