In most forecasting packages there are two transformations easily available for stabilizing variance: the square root and the logarithnic. Is there any procedure (e.g. test) that can tell the user which one of the two transformations to choose? Finally, the variance stabilization transofrmation should be apllied to time series data (if they exhibit multiplicative variance) no matter what is the model to be used (e.g. it should be used in ARIMA, exponential smoohting, unobserverd components, classical decomposition etc if the time series exhibit multiplicative variance)?
Thnaks in advance,