2.2.1. Normalising the variable

The normalisation function can be called to create new variables, for every requested normalisation, whose range and dispersion depend on the chosen normalisation method. Up to now, there are four different ways to perform this normalisation:

• centered-reducted: the new variable values are computed as \(\tilde{x} = \dfrac{x - \mu_{x}}{\sigma_{x}}\)

• centered: the new variable values are computed as \(\tilde{x} = x - \mu_{x}\)

• reduced to \([-1,1]\): the new variable values are computed as \(\tilde{x} = 2.0 \times \dfrac{ x - x_{\rm Min}}{x_{\rm Max} - x_{\rm Min}} -1.0\)

• reduced to \([0,1]\): the new variable values are computed as \(\tilde{x} = \dfrac{ x - x_{\rm Min}}{x_{\rm Max} - x_{\rm Min}}\)