The diameter of a wire outgt to be 8 cm. It follows a normal distribution and has a standard deviation of 0.01 cm.
A buyer tests each delivery by taking 5 samples, accepting the goods only if the mean is at most 8.01.
(I have solved part a) which is to find alpha)
b)
New assumptions:
A hypothesis test is to be carried out with P(type I error) = P(type II error) and either one being at most 0.1%.
What is the necessary sample size (at least) to do this test? (answer in my book says it's n >= 17)
I know x-bar critical = Mu(0) + or - z(a) * s(x-bar)
and that to solve for Beta, the true population proportion is needed, but since it isn't given here and I don't know alpha, I don't know really where to start. Could anyone get me started on this, that would be greatly appreciated as I've really tried but I always get the wrong answer.
Thanks!
A buyer tests each delivery by taking 5 samples, accepting the goods only if the mean is at most 8.01.
(I have solved part a) which is to find alpha)
b)
New assumptions:
A hypothesis test is to be carried out with P(type I error) = P(type II error) and either one being at most 0.1%.
What is the necessary sample size (at least) to do this test? (answer in my book says it's n >= 17)
I know x-bar critical = Mu(0) + or - z(a) * s(x-bar)
and that to solve for Beta, the true population proportion is needed, but since it isn't given here and I don't know alpha, I don't know really where to start. Could anyone get me started on this, that would be greatly appreciated as I've really tried but I always get the wrong answer.
Thanks!