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Help! - boxcox transformations
2 messages · Nuno Prista, Peter Dunn
I am trying to detrend and transform variables to achieve normality and stationarity (for time series use, namely spectral analysis). I am using the boxcox transformations. As my dataset contains zeros, I found I need to add a constant to it in order to run "boxcox".
If your data are continuous with exact zeros, and contain a lot of zeros, no transformation may help. You simply map a stack of zeros to some other value. Box--Cox transforms are not really designed for this. If your data really is continuous with exact zeros, other options exist such as hurdle models, Tweedie glms (package tweedie) and so forth. P.
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