Question

If random samples of size 11 are drawn from a population with mean 7 and standard deviation 2 , find the standard error of the distribution of sample means.

Round your answer to three decimal places, if necessary.

standard error =

Assume the sample is a random sample from a distribution that is reasonably normally distributed and we are doing inference for a sample mean. Find endpoints of a t-distribution with 1% beyond them in each tail if the sample has size n=19.

Round your answer to three decimal places.

endpoints  = ±

Answer 1

Question 1

If random samples of size 11 are drawn from a population with mean 7 and standard deviation 2 , find the standard error of the distribution of sample means.

Standard error = SD/sqrt(n)

We are given

SD = 2

n = 11

Standard error = 2/sqrt(11)

Standard error = 0.603023

Question 2

Assume the sample is a random sample from a distribution that is reasonably normally distributed and we are doing inference for a sample mean. Find endpoints of a t-distribution with 1% beyond them in each tail if the sample has size n=19.

We are given

n = 19

df = n – 1 = 18

α/2 = 0.01

So, t values by using t-table are given as below:

Endpoints = ± 2.552