Hand Coding the Power of a Test
We want to test if our population average is different from twenty.
We therefore specify the follow zero hypothesis.
\[H_0: \mu = 20\]The alternative hypothesis is
\[H_a: \mu \neq 20\]Accepting
mu <- 40
sd <- 8
n <- 20
ci <- qnorm(0.975)*sd/sqrt(n)
(left <- mu - ci)
## [1] 36.49391
(right <- mu + ci)
## [1] 43.50609