# Conditional and Total Variance

• October 17th 2010, 08:32 AM
Time
Conditional and Total Variance
What is an intuitive explanation of why $\text{Var}(Y) = E(\text{Var}(Y|X)) + \text{Var}(E(Y|X))$? In laymen terms, it is equal to the variance of the conditional expectation plus the expected value of the conditional variance.
• October 17th 2010, 03:44 PM
yannyy
my lecturer told me that there is no simple intuitive explanation to this and it has a complex proof to it as well.

Law of total variance - Wikipedia, the free encyclopedia

Theres a proof in there
• October 17th 2010, 03:45 PM
yannyy
my lecturer told me that there is no simple intuitive explanation to this and it has a complex proof to it as well.

Law of total variance - Wikipedia, the free encyclopedia

Theres a proof in there