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Computing Weighted Average

AquaNX4Nov 21 2018 — edited Nov 21 2018

Hello:

I've researched how to calculate a weighted average and I understand it very well.  However, there is one aspect I need clarification and confirmation on.  An "Oracle SQL Weighted Averages" search online 99.9% of the time suggests to use the following formula for getting a weighted average:

sum ( column_of_value * column_of_weight ) / sum ( column_of_weight ) which is suggested here Average Weight in Oracle and from many other results.

This is where I need clarification: If the sum of my identify for the weights of each number will always equal one (1) which is 100%, do I need to divide by the sum(column_of_weight)?  It would appear to be a redundant step since the result of that computation will always equal sum ( column_of_value * column_of_weight ).

I'm just confirming that the sum of a weighted score will always equal the same value if the sum of the weights ascribed equals one (1).

Thanks,

Aqua

This post has been answered by mathguy on Nov 21 2018
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Added on Nov 21 2018
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