I understand that the F-test sets the independent variables, as a group, to explain the variabtion in the dependent variable But, what is the logic behind setting the values of the independent variables to zero (0)?
gazhoo Wrote:
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> hi Rusbus,
>
> when you say "If all of these coefficients
> together come out to be statistically 0..." what
> do you mean exactly?
>
> the null is trying to prove that all the
> coefficients = 0. If they do, this means that the
> F-value will lie outside the critical F value?
F-test is a one sided test. Fstat is greater than or less than Fcrit = accept null hypothesis regression is insignificant.
You reject the null if the F stat is greater than the critical value determined from the F table. The null hypothesis is that the test parameters do NOT explain the model. Therefore if you reject the null, you are saying that the independant variables (as a group) do explain the dependant variable to some extent. If you fail to reject the null, it means that the independant variables do not explain the dependant one.