Question
In: Statistics and Probability
The publisher of a regional telephone book surveyed a simple random sample of 10 of its...
The publisher of a regional telephone book surveyed a simple random sample of 10 of its commercial yellow-page ad customers to determine whether the size of their ads in square inches were correlated with the proportion of calls to the business that were generated by the ads.
|
a. Calculate the correlation coefficient |
| b. Calculate the coefficient of determination |
What percentage of the variation in the proportion of calls generated by the ad is explained by the size of the ad in square inches?
Is the correlation coefficient significantly greater than zero at the 5% significance level?
| Respondent # | Ad size in sq inches (X) | % of calls generated by the ad (Y) | X*Y | X2 | Y2 |
| 1 | 9 | 13% | 1.17 | 81 | 0.017 |
| 2 | 16 | 16% | 2.56 | 256 | 0.026 |
| 3 | 25 | 21% | 5.25 | 625 | 0.044 |
| 4 | 16 | 18% | 2.88 | 256 | 0.032 |
| 5 | 20 | 18% | 3.60 | 400 | 0.032 |
| 6 | 16 | 19% | 3.04 | 256 | 0.036 |
| 7 | 20 | 15% | 3.00 | 400 | 0.023 |
| 8 | 20 | 17% | 3.40 | 400 | 0.029 |
| 9 | 16 | 13% | 2.08 | 256 | 0.017 |
| 10 | 9 | 11% | 0.99 | 81 | 0.012 |
Solutions
orchestra answered 2 years agoRelated Solutions
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the country surveyed a simple random sample of 421 California
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Among other observations, the investigators noted that
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