DAX: how to use measures instead of calculated columns?

bartvana 

You calculate average of average here. The pattern for such calculation is using of AVERAGEX / SUMMARIZE.

Measures could be as

Avr Of Mean Measure:=VAR sumCat=
    SUMMARIZE (
        tFacts,
        tFacts[Category],
        tFacts[Product],
        "sumQtyOnMonth", SUMX ( tFacts, tFacts[AvgQty] * tFacts[Month] ),
        "sumQty",    SUM ( tFacts[AvgQty] )
    )
VAR Result=
    AVERAGEX ( 
       sumCat,
       DIVIDE ( [sumQtyOnMonth], [sumQty] )
    )
RETURN Result

and

Avr Of StDev Measure:=AVERAGEX (
    SUMMARIZE (
        tFacts,
        tFacts[Category],
        tFacts[Product],
        "variance",
            SUMX (
                tFacts,
                (
                     tFacts[AvgQty]
                        - CALCULATE ( [Avr Of Mean Measure], ALLEXCEPT ( tFacts, tFacts[Product] ) )
                ) ^ 2
           )
               / SUM ( tFacts[AvgQty] )
     ),
     SQRT ( [variance] )
)

Compare to current measures result is