If variance changes over time it is suggested you log the data. I can never figure out if the variance is changing. This is the raw data (if it matters the data ends up being a seasonal arima which differences). The ARIMA that was chosen by auto.arima (when I did not log the data) was ARIMA(0,1,1)(1,0,0)[12]
If its suggested that I log the data, how do I log it and convert it back when I do the forecast statement in R (in the library forecast ideally)?
If its suggested that I log the data, how do I log it and convert it back when I do the forecast statement in R (in the library forecast ideally)?
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