10.30 Rescale Data using Recenter in Rattle
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A common normalisation is to recenter our data. The simplest approach to do this is to subtract the mean value of a variable from each observation’s value of the variable (to recenter the variable) and to then divide the values by the standard deviation of the variable values, which rescales the variable back to a range of values having a mean of zero and standard deviation of 1.
Rattle relies on the base::scale() function from the base package to perform the re-centering:
Note that the resulting mean is not precisely zero due to the precision of the calculations, but pretty close. The resulting standard deviation is generally exactly 1.
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