What is the name of this data normalization?

Question

I have a two-dimensional array ($569\times30$ double) which should be normalized using this formula:

$x'_{ij} = \dfrac{x_{ij} - \overline\mu_j}{\overline\delta_j} $

What is the name of this normalization and how can I do that in Matlab?

Answer 1

This transformation is called Z-score (see wikipedia entry). It can be implemented easily in Matlab, just take a look on zscore function. Please notice, that the result depends on how you store your data (if samples are stored in the rows or in the columns).