SAMPLE VARIANCE QUESTION/ HYP. TEST QUESTION . ):

Question

A sample is selected from a population with mu = 80 and a treatment is administered to the sample. If the sample variance is s2 (s-squared) = 20, which set of sample characteristics is most likely to lead to a decision that there is a significant treatment effect?

 

M = 85 for a sample of n = 100
M = 90 for a sample of n = 100
M = 85 for a sample of n = 25
M = 90 for a sample of n = 25

The results of a hypothesis test are reported as follows: t(18) = 2.25, p < .05. Based on this report, what was the statistical decision and how big was the sample? The null hypothesis was rejected using a sample of n = 19. The null hypothesis was not rejected using a sample of n = 19. The null hypothesis was not rejected using a sample of n = 18. The null hypothesis was rejected using a sample of n = 18.

Answer 1

M = 90 for a sample of n = 100