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rsbin's avatar
rsbin
Community Champion
6 years ago
Solved

Moving Average -> Standard Deviation

Good Morning, Reaching out to the DAX experts out there.  I am trying to calculate the Standard Deviation of a Measure based on a 3 Day Moving Average (i.e. 3DayStdDev_EquipIDRatio).  My sample data...
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  • Icey's avatar
    Icey
    6 years ago

    Hi rsbin ,

     

    How about using ALLSELECTED in the expression?

    3DayStdDev_EquipIDRatio =
VAR CurrentIndex =
    MAX ( GeneralStatistics[GSIndex] )
VAR PreviousIndex = CurrentIndex - 2
VAR _table =
    SUMMARIZE (
        FILTER (
            ALLSELECTED (GeneralStatistics ),   ------------------edited
            GeneralStatistics[TotalVisits] <> 0
                && GeneralStatistics[GSIndex] >= PreviousIndex
                && GeneralStatistics[GSIndex] <= CurrentIndex
        ),
        [Date],
        "_EquipIDRatio", [EquipmentIDRatio]
    )
RETURN
    STDEVX.P ( _table, [_EquipIDRatio] )

     

     

    Best Regards,

    Icey

     

    If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.

Icey's avatar
Icey
Community Support
6 years ago

Hi rsbin ,

 

How about this?

3DayStdDev_EquipIDRatio =
VAR CurrentIndex =
    MAX ( GeneralStatistics[GSIndex] )
VAR PreviousIndex = CurrentIndex - 2
VAR _table =
    SUMMARIZE (
        FILTER (
            GeneralStatistics,
            GeneralStatistics[TotalVisits] <> 0
                && GeneralStatistics[GSIndex] >= PreviousIndex
                && GeneralStatistics[GSIndex] <= CurrentIndex
        ),
        [Date],
        "_EquipIDRatio", [EquipmentIDRatio]
    )
RETURN
    STDEVX.P ( _table, [_EquipIDRatio] )

 

 

Best Regards,

Icey

 

If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.

rsbin's avatar
rsbin
Community Champion
6 years ago

Good Morning Icey 

Thanks much for the reply.   I have attempted that code as as Solution, but it returns only an answer for the last date.

 

The ".03142" is the correct answer for Index = 7.   I too thought it would cycle through and provide an answer for each Index, but as you can from the above, it Returns just a single value.

I got up this morning thinking "CALCULATETABLE" might be the way to proceed.   Really appreciate you taking the time to respond. If you have further suggestions I would be grateful to hear them.  Kudos for the attempt.

 

Kind Regards,

  • Icey's avatar
    Icey
    Community Support
    6 years ago

    Hi rsbin ,

     

    How about using ALLSELECTED in the expression?

    3DayStdDev_EquipIDRatio =
VAR CurrentIndex =
    MAX ( GeneralStatistics[GSIndex] )
VAR PreviousIndex = CurrentIndex - 2
VAR _table =
    SUMMARIZE (
        FILTER (
            ALLSELECTED (GeneralStatistics ),   ------------------edited
            GeneralStatistics[TotalVisits] <> 0
                && GeneralStatistics[GSIndex] >= PreviousIndex
                && GeneralStatistics[GSIndex] <= CurrentIndex
        ),
        [Date],
        "_EquipIDRatio", [EquipmentIDRatio]
    )
RETURN
    STDEVX.P ( _table, [_EquipIDRatio] )

     

     

    Best Regards,

    Icey

     

    If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.

    • rsbin's avatar
      rsbin
      Community Champion
      6 years ago

      Good Morning Icey 

       

      Yes, the edit works.  I finally am able to get the Std. Dev values for each Index.   Thank you very much for the assistance.

       

      Unfortunately, still having some issues having it display properly in my line charts.   I have to figure out why it is behaving like that.

      But thanks again, it is a relief to finally solve the first part of this.

       

      Kind Regards and all the best,