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
1 750 125
2 1,000 145
3 1,750 204
4 2,000 132
5 1,500 108
6 1,000 51
7 1,250 232
8 750 128
9 2,000 297
10 1,250 271
11 1,500 41
12 1,750 275
13 2,000 285
14 2,000 259
15 1,500 156
16 1,250 252
17 750 61
18 750 72
19 1,500 41
20 1,250 164
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 0.025 significance level. (Round intermediate calculations and final answer to 3 decimal places.)
H0: rho ≤ 0; H1: rho > 0 Reject H0 if t > 2.101
Develop the regression equation for effective heating based on wattage. (Negative value should be indicated by a minus sign. Round your answers to 3 decimal places.)
Which heater looks like the "best buy" based on the size of the residual? (Round residual value to 3 decimal places.)