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32 . Explain in words what it means that a screening test for TB has an α level of 0.10. The null hypothesis is that the patient does not have TB.
33 . Explain in words what it means that a screening test for TB has a β level of 0.20. The null hypothesis is that the patient does not have TB.
34 . Explain in words what it means that a screening test for TB has a power of 0.80.
35 . If you are conducting a hypothesis test of a single population mean, and you do not know the population variance, what test will you use if the sample size is 10 and the population is normal?
36 . If you are conducting a hypothesis test of a single population mean, and you know the population variance, what test will you use?
37 . If you are conducting a hypothesis test of a single population proportion, with np and nq greater than or equal to five, what test will you use, and with what parameters?
38 . Published information indicates that, on average, college students spend less than 20 hours studying per week. You draw a sample of 25 students from your college, and find the sample mean to be 18.5 hours, with a standard deviation of 1.5 hours. What distribution will you use to test whether study habits at your college are the same as the national average, and why?
39 . A published study says that 95 percent of American children are vaccinated against measles, with a standard deviation of 1.5 percent. You draw a sample of 100 children from your community and check their vaccination records, to see if the vaccination rate in your community is the same as the national average. What distribution will you use for this test, and why?
40 . You are conducting a study with an α level of 0.05. If you get a result with a p-value of 0.07, what will be your decision?
41 . You are conducting a study with α = 0.01. If you get a result with a p -value of 0.006, what will be your decision?
Use the following information to answer the next five exercises. According to the World Health Organization, the average height of a one-year-old child is 29”. You believe children with a particular disease are smaller than average, so you draw a sample of 20 children with this disease and find a mean height of 27.5” and a sample standard deviation of 1.5”.
42 . What are the null and alternative hypotheses for this study?
43 . What distribution will you use to test your hypothesis, and why?
44 . What is the test statistic and the p -value?
45 . Based on your sample results, what is your decision?
46 . Suppose the mean for your sample was 25.0. Redo the calculations and describe what your decision would be.
47 . You conduct a study using α = 0.05. What is the level of significance for this study?
48 . You conduct a study, based on a sample drawn from a normally distributed population with a known variance, with the following hypotheses:
H
0 :
μ = 35.5
H
a :
μ ≠ 35.5
Will you conduct a one-tailed or two-tailed test?
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