A consumer buying cooperative tested the effective heating areaof 20 different electric space heaters with different wattages.Here are the results.
Heater | Wattage | Area |
1 | 1,250 | | 365 | |
2 | 1,750 | | 455 | |
3 | 2,000 | | 545 | |
4 | 1,800 | | 455 | |
5 | 1,500 | | 355 | |
6 | 1,250 | | 354 | |
7 | 300 | | 65 | |
8 | 1,000 | | 35 | |
9 | 600 | | 45 | |
10 | 1,000 | | 55 | |
11 | 300 | | 65 | |
12 | 2,250 | | 545 | |
13 | 300 | | 55 | |
14 | 950 | | 55 | |
15 | 300 | | 25 | |
16 | 400 | | 35 | |
17 | 800 | | 55 | |
18 | 240 | | 65 | |
19 | 1,800 | | 455 | |
20 | 300 | | 25 | |
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a. Compute the correlation between the wattage and heating area.Is there a direct or an indirect relationship? (Negativevalue should be indicated by a minus sign. Round your answer to 3decimal places.)
The correlation of Wattage and Area is _______.
b. Conduct a test of hypothesis to determine if it is reasonablethat the coefficient is greater than zero. Use the 0.05significance level. (Negative value should be indicated bya minus sign. Round intermediate calculations and final answer to 3decimal places.)
H0: Ï â‰¤ 0; H1: Ï > 0Reject H0 if t > 1.7341
t=______
C. Develop the regression equation for effective heatingbased on wattage. (Negative value should beindicated by a minus sign. Round your answers to 3 decimalplaces.)
The regression equation is Area=______+______Wattage
D. Which heater looks like the “best buy†based on thesize of the residual? (Negative value should beindicated by a minus sign. Round residual value to 2 decimalplaces.)
The fifth heater is the \"best buy.\" It heats an area that is________ square feet larger than estimated by the regressionequation.