Identify Bi-Modal Distribution

Hi there,

I want to analyse measurement data in terms of unwanted Bi-Modal distribution of a certain value. Is there a node available which I can use?

Andreas

I don’t think we have a node that performs this type of test directly, but then again I also don’t think I’m fully understanding your question.

Maybe you could post some example data, and describe in a bit more detail what it is you’re trying to do?

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There is an R package that seems to be helping with that. ‘modes’

https://cran.r-project.org/web/packages/modes/modes.pdf

You could use that in KNIME and see if you can use the statistics that are provided by this package to make a decision. It also creates a plot where you can visually inspect if there is a Bi-Modal distribution. You might adapt that to test for further distributions.

Please note I am not an expert in these statistics, just built them into a workflow :slight_smile:. The description for the package for example states that for the:

bimodality_coefficient - "The bimodality coefficient has a range of zero to one (that is: [0,1]) where a value greater than “5/9” suggests bimodality. "

So with 0.774 being larger than 0.556 the statistic here would indicate that the distribution is bimodal. And the visual inspection seems to support that.

I was toying around with creating a variable to bring the description into the graphic but gave up for now. You might include that ins some future graphic you might create.

kn_example_r_bimodality.knar (325.7 KB)

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Wow, that is what I was looking for!

edit: And it works like a charme. Brilliant

Thank you

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