Forum Discussion

TMO_KY's avatar
TMO_KY
Helper II
2 years ago

StDev discrepancy when using similar tables

I wasn't exactly sure how to word my problem to make it stand out from similar but different issues.  Anyway, I have a DAX table that I created and it works flawlessly but I was recently asked if I c...
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lbendlin's avatar
lbendlin
Super User
2 years ago

Please provide sample data (with sensitive information removed) that covers your issue or question completely, in a usable format (not as a screenshot). Leave out anything not related to the issue.
https://community.fabric.microsoft.com/t5/Community-Blog/How-to-provide-sample-data-in-the-Power-BI-Forum/ba-p/963216
Please show the expected outcome based on the sample data you provided.

https://community.fabric.microsoft.com/t5/Desktop/How-to-Get-Your-Question-Answered-Quickly/m-p/1447523

  • TMO_KY's avatar
    TMO_KY
    Helper II
    2 years ago

    Ive uploaded a pbix file with sample data to my dropbox.  Hope this helps.

    StDev_SampleData.pbix 

    • lbendlin's avatar
      lbendlin
      Super User
      2 years ago

      In your TEST table each failure has its own row, therefore the standard deviation is computed across all these 1 values. You need to use STDEVX.P rather than STDEV.P 

       

      Having said that I can only get half of it to work.

       

       

      • TMO_KY's avatar
        TMO_KY
        Helper II
        2 years ago

        That's more than where I was able to get so I appreciate it.  I'll have to talk to my end user and get their thoughts. if the Product Family will be in a visual or not.  I know it's used as a filter sometimes but not always.

        What if there was a sum measure for the Failures in the test table and do the stdevx against a measure?