Question

Assume that the data has a normal distribution and the number of observations is 24. Find the critical t value used to test a null hypothesis.

α = 0.05 for a left-tailed test

Answer 1

Assume that the data has a normal distribution and the number of observations is 24. Find the critical t value used to test a null hypothesis.

This is a test for a population mean. Since pop SD is unknown and the data is assumed to be normal, we will use the t-dist.

n = 24

α = 0.05 for a left-tailed test

Since this is a left tailed we check on the left side and C.V. will be negative.

We reject the null hypothesis if Test Stat < C.v.

C.V. = t_α,n-1

= t_0.05,23

C.V. = 1.7139 ...................using the t-dist tables df = n-1 = 23 , p =α = 0.05

Due to being left tailed

C.V. = -1.7139

We reject the null hypothesis if Test Stat < -1.7139 or |Test stat| > 1.7139