In: Statistics and Probability
Questions 10 through 15 refer to the following:
The following data concerning income and educational attainment for several counties in Alabama were taken from the U.S. Census Website.
County |
% High School Grads |
Per Capita Income |
Autauga |
87.6 |
26168 |
Chilton |
80.1 |
22045 |
Coosa |
72.9 |
18080 |
Dallas |
79.0 |
17611 |
Elmore |
86.8 |
24711 |
Jefferson |
89.0 |
28162 |
Lee |
88.7 |
24951 |
Lowndes |
74.8 |
18434 |
Macon |
80.5 |
18385 |
Montgomery |
85.5 |
26255 |
Pike |
80.0 |
20180 |
Shelby |
91.6 |
34117 |
Sum |
996.5 |
279,099 |
Sum of Squares |
83,144.21 |
6,772,411,831 |
∑xy |
23,475,084.2 |
10.Find the least squares regression equation for predicting per capita income using the percentage of high school graduates.
y = 419082.121 - 57.439x |
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y = -39729.72 + 758.510x |
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y = -6652.046 + 317.053x |
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y = -18096.537 + 474.365x |
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y = 22417.029 + 127.884x |
QUESTION 11
Find the sample correlation coefficient between per capita income and percentage of high school graduates.
QUESTION 12
Find the value of the t statistic for testing H0: β1 = 0 vs. HA: β1 ≠ 0.
QUESTION 13
What's the p-value for the test statistic in #12?
QUESTION 14
Do the data provide significant evidence at the .05 level of a linear relationship between per capita income and the percentage of high school graduates?
yes |
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no |
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12 |
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robot |
QUESTION 15
What is the expected change in per capita income associated with a 1% increase in the proportion of high school graduates?