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Normalization

DocMusherDocMusher Member Posts: 333 Unicorn
edited November 2018 in Help
Hi,

A dataset of 20 samples from 3 time points (54 attributes per time point)
Normalization should be performed on the subset from each time point right? or on the entire data set?
The aim is to analyse changes of attributes between 3 points.

Which python or R plot best illustrates changes for that few samples vs attributes? Anyone a better way to illustrate?
https://beckmw.wordpress.com/2013/04/01/a-nifty-line-plot-to-visualize-multivariate-time-series/

Cheers
Sven

Answers

  • David_ADavid_A Administrator, Moderator, Employee-RapidMiner, RMResearcher, Member Posts: 297 RM Research
    Hi Sven,

    when to normalize should really depend on what you want to compare.
    If you compare within your sampling, then normalization within the sample is fine.
    But if comparing different samples, then this might give false impressions.
    The process below shows the differences.
    I hope this clearifies your question.

    BTW I like your plots a lot and they are good example of data visualization and to tell the story of these data. I would only option to choose only a few species, with all 25 (as in the first example) it is simply too much information in single plot.

    Best,
    David
    <?xml version="1.0" encoding="UTF-8" standalone="no"?>
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  • DocMusherDocMusher Member Posts: 333 Unicorn
    David,
    thanks!
    Sven
  • DocMusherDocMusher Member Posts: 333 Unicorn
    Per time point a sample generate features having different units. Different time points are compared. Normalization per time point or on the complete dataset, what is the right choice.
    Thanks
    Sven
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