In: Statistics and Probability
Exercise 13-58 (LO13-2, LO13-3)
A consumer buying cooperative tested the effective heating area of 20 different electric space heaters with different wattages. Here are the results.
| Heater | Wattage | Area | ||
| 1 | 750 | 168 | ||
| 2 | 750 | 58 | ||
| 3 | 1,500 | 56 | ||
| 4 | 750 | 51 | ||
| 5 | 1,000 | 237 | ||
| 6 | 1,250 | 105 | ||
| 7 | 1,000 | 139 | ||
| 8 | 2,000 | 197 | ||
| 9 | 1,250 | 80 | ||
| 10 | 1,500 | 166 | ||
| 11 | 750 | 75 | ||
| 12 | 1,750 | 292 | ||
| 13 | 2,000 | 49 | ||
| 14 | 1,250 | 78 | ||
| 15 | 1,750 | 269 | ||
| 16 | 750 | 162 | ||
| 17 | 1,250 | 171 | ||
| 18 | 1,500 | 147 | ||
| 19 | 2,000 | 244 | ||
| 20 | 1,000 | 73 | ||
Compute the correlation between the wattage and heating area. Is there a direct or an indirect relationship? (Round your answer to 4 decimal places.)
Conduct a test of hypothesis to determine if it is reasonable that the coefficient is greater than zero. Use the 0.050 significance level. (Round intermediate calculations and final answer to 3 decimal places.)
Develop the regression equation for effective heating based on wattage.