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ahmohamed / lipidr

Data Mining and Analysis of Lipidomics datasets in R
https://www.lipidr.org/
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Normalized? #41

Closed DavidGO464 closed 1 year ago

DavidGO464 commented 1 year ago

Just to make sure,

when as_lipidomics_experiment asks if the data is "normalized", it is NOT referring to "standardization", right?

with "standardization", I mean a mean of 0 (zero) and SD of 1.

I ask this because in data science it is pretty common to use both terms interchangeably

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ahmohamed commented 1 year ago

Normalization is defined as used in 'omics analysis, which means that samples have similar distributions. It doesn't imply zero-centered means or unit variance scaling. The latter is not needed for differential analysis.

NB: some internal functions in lipidr will perform scaling where needed. One example is the mva function for PCA and OPLS. You don't need to worry about that though.