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ask's avatar
ask
Helper III
9 years ago

Standard Diviation

I have a set of data for student's score for 2 years. i will get the standardard deviation of list of student on picked day. how to do that?  Output will look like this.    Name Score Standard...
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ask's avatar
ask
Helper III
9 years ago

Anonymous  the column of "STANDARD DEVIATION OF WELLNESS SCORE", I use the built in function of power bi which is the simply way you mentioned.,

 

The column of Score STDEV.P  comes from the calculation : Score SD = CALCULATE(STDEV.P(data[Score]),ALLEXCEPT(data, data[Score], data[Name]))

 

are they supposed to be the same?

 

NameScoreStandard deviation of Wellness Score Score STDEV.P
NAME 176808
NAME 2273018
NAME 3190038
NAME 49607
NAME 594014
NAME 69608
NAME 79801
NAME 89805
NAME 99602
NAME 108608
v-ljerr-msft's avatar
v-ljerr-msft
Microsoft Employee
9 years ago

Hi ask,

 

Based on my test, the build-in standard deviation function should be similar to just using the STDEV.P function without any other filters like below. :smileyhappy:

Score SD = STDEV.P(data[Score])

 

 

Regards

  • ask's avatar
    ask
    Helper III
    9 years ago

    v-ljerr-msft have you tried to pick the specific date. for example every wednesday for the past 2 years?  How to do that?

     

     

     

    • v-ljerr-msft's avatar
      v-ljerr-msft
      Microsoft Employee
      9 years ago

      Hi ask,

       

      The formula below should work. :smileyhappy:

      Score SD =
CALCULATE (
    STDEV.P ( data[Score] ),
    FILTER ( data, WEEKDAY ( data[Date] ) = 4 && YEAR ( data[Date] ) >= 2015 )
)

       

      Regards

      • ask's avatar
        ask
        Helper III
        9 years ago

        v-ljerr-msft How about to check the dynamic date instead of wednesday, that might be Tuesday, Monday, etc, and also dynamic name selected.

         

        Score SD =
CALCULATE (
    STDEV.P ( data[Score] ),
    FILTER ( data, WEEKDAY ( data[Date] ) = 4 && YEAR ( data[Date] ) >= 2015 )
)