Question

You have an SRS of size 8 and calculate the one-sample t statistic. What is the critical value t∗ such that (a) t has probability 0.02 to the right of t∗? (b) t has probability 0.85 to the left of t∗?

Answer 1

a) "=T.INV(1-0.02,7)"

And we got
`t_(crit)= 2.518`

b) "=T.INV(0.85,7)"

And we got
`t_(crit)= 1.119`

Explanation:

For this case we have a sample size of n=8, so we can find the degrees of freedom like this:

`df = n-1 = 8-1 =7`

Part a

For this case we need a value who accumulates 0.02 of the area in the right of the t distribution with 7 degrees of freedom so we can use the following excel code:

"=T.INV(1-0.02,7)"

And we got
`t_(crit)= 2.518`

Part b

For this case we need a value who accumulates 0.85 of the area in the left of the t distribution with 7 degrees of freedom so we can use the following excel code:

"=T.INV(0.85,7)"

And we got
`t_(crit)= 1.119`