Quiz 7 Hypothesis testing of single samples z-test and t-test

1. Which of the following pair of statistical hypotheses is NOT valid? a) H0: μ = 82 kg H1: μ ≠ 82 kg b) H0: μ ≥ 82 kg H1: μ < 82 kg c) H0: μ < 82 kg H1: μ > 82 kg d) H0: μ ≤ 82 kg H1: μ > 82 kg

2. The diagram at bottom is an example of a ________ test. a) one-tailed, right b) two-tailed c) directional d) one-tailed, left

3. What does a mean? a) probability of a Type I error b) probability of a Type II error c) power of a statistical test d) area in non-critical region

4. Power of a statistical test is defined _______. a) by 1 — a b) by b c) as chance of getting a Type I error d) as the ability to detect a real difference

5. The z-distribution should be used to test a sample mean when ______. a) s is known b) sample size is < 30 c) data are not normally distributed d) sample size is > 30

6. The t-test for testing a single sample mean may be used when all of the following conditions are true excepting _______. a) data are approximately normally distributed b) population SD (s) is known c) sample size less than 30 d) sample SD (s) is known

7. Given a population with mean 12. 5 seconds and SD of 2 7. Given a population with mean 12.5 seconds and SD of 2.5 s, calculate the test value of a sample of 20 people with a mean of 13.6 s representative of the population? Use a=0.05. a) -1.100 b) -1.968 c) 1.968 d) 1.100

8. A sample of 12 scores has a mean of 25. 0 newtons with SD of 5. 8 N 8. A sample of 12 scores has a mean of 25.0 newtons with SD of 5.8 N. Given a pop. mean of 30.0 N what test value should be use to test whether it is the same as the pop. mean (a=0.05)? a) 8.37 b) 1.783 c) -1.783 d) -5.00