Problem 1
Use the following information to answer the next three exercises. Suppose a group is interested in determining whether teenagers obtain their drivers licenses at approximately the same average age across the country. Suppose that the following data are randomly collected from five teenagers in each region of the country. The numbers represent the age at which teenagers obtained their drivers licenses.
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Northeast
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South
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West
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Central
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East
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16.3
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16.9
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16.4
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16.2
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17.1
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16.1
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16.5
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16.5
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16.6
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17.2
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16.4
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16.4
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16.6
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16.5
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16.6
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16.5
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16.2
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16.1
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16.4
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16.8
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x =
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S2 =
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Table
Ho: μ1 = μ2 = μ3 = μ4 = μ5
Hα: At least any two of the group means μ1, μ2, μ5 are not equal.
degrees of freedom - numerator: df(num)=
Problem 2. (use the same information from problem 1)
F statistic =
Problem 3. A researcher wants to know if the mean times (in minutes) that people watch their favorite news station are the same. Suppose that Table shows the results of a study.
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CNN
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FOX
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Local
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45
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15
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72
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12
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43
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37
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18
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68
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56
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38
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50
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60
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23
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31
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51
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35
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22
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Table
Assume that all distributions are normal, the four population standard deviations are approximately the same, and the data were collected independently and randomly. Use a level of significance of 0.05.
Problem 4.
Are the mean number of times a month a person eats out the same for whites, blacks, Hispanics and Asians? Suppose that Table shows the results of a study.
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White
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Black
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Hispanic
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Asian
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6
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4
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7
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8
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8
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1
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3
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3
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2
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5
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5
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5
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White
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Black
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Hispanic
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Asian
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4
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2
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4
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1
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6
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6
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7
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Table
Assume that all distributions are normal, the four population standard deviations are approximately the same, and the data were collected independently and randomly. Use a level of significance of 0.05.