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standard deviation per Article - XYZ-analysis - Help please ?

StudentNeedHelpStudentNeedHelp Member Posts: 7 Learner I

Hello everybody,

I just wanted to do an XYZ analysis, but I fail because of the standard deviation ...

This is what the simplified example looks like:

 

 

At the end I need a standard deviation per article…. But I do not know how to enter it….

So far, I have grouped the articles so that article 1 only has one entry and the quantity has 60. If I then do the standard deviation, every line comes up with 0 ...

Does anyone have any idea how I can calculate the standard deviation for each article?

Many thanks

Best regards

 

David

Best Answer

  • ceaperezceaperez Member Posts: 541 Unicorn
    Solution Accepted
    Hi @StudentNeedHelp
    please read the definition of standard deviation. 
    in you sampleset you have only one sample per article, so the mean is the same number and the difference between the sample and mean is zero, so the standard deviation is zero also.

    Standard deviation - Wikipedia

    if you try to run the process with more than one sample per article  (with different values) you will obtain a  non zero standard deviation



    Best

Answers

  • ceaperezceaperez Member Posts: 541 Unicorn
    Hi @StudentNeedHelp,

    you can work with Aggregate Operator. There you have a lot of functionalities, also standard deviation.

    Best
  • StudentNeedHelpStudentNeedHelp Member Posts: 7 Learner I
    Yes, but it didn´t work.... so i dont know how to use  a standard deviation per article
  • ceaperezceaperez Member Posts: 541 Unicorn
    Hi @StudentNeedHelp

    working with the dataset that you shown, a possible configuration for the Aggregate Operator can be:

    the aggregation attributes -> Amount
    aggregation function -> standard_deviation

    in group by attributes select -> Article.

    please find attached a simple sample.

    regards
  • StudentNeedHelpStudentNeedHelp Member Posts: 7 Learner I
    Thanks for your example, but it is still the same problem.... the standard_standard_deviation in every row is 0.... and I dont know why.....



    Any idea?

    best,

    David
  • StudentNeedHelpStudentNeedHelp Member Posts: 7 Learner I
    Thanks a lot. I found my mistake, my article were already groupedy a few steps before, so I only had one Value. 
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