Why we need variance in this world?
What is the purpose to make such function and how does it work?
I know that it is a measure of how the data spread, but why we don't just use the absolute variation to solve this problem?
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Sign up to join this communityWhy we need variance in this world?
What is the purpose to make such function and how does it work?
I know that it is a measure of how the data spread, but why we don't just use the absolute variation to solve this problem?
Or: Why do we need watermelons if we have rib eye steaks?
They are different things. There are many measures of dispersion which provide information about different features of a distribution.
A single number hardly summarises all the information about the shape of a distribution.