Question

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	1,580		194
2	650		73
3	1,510		202
4	1,240		138
5	1,180		154
6	1,320		207
7	1,000		109
8	1,910		272
9	1,100		134
10	1,450		192
11	1,160		87
12	420		44
13	400		81
14	1,410		187
15	1,950		221
16	1,600		206
17	690		71
18	1,420		202
19	1,290		129
20	420		58

Click here for the Excel Data File

1. Compute the correlation between the wattage and heating area. Is there a direct or an indirect relationship? (Negative value should be indicated by a minus sign. Round your answer to 3 decimal places.) The correlation of the cottage and area is_____. The link (relationship) is_____

2. Conduct a test of hypothesis to determine if it is reasonable that the coefficient is greater than zero. Use the 0.01 significance level. (Negative value should be indicated by a minus sign. Round intermediate calculations and final answer to 3 decimal places.)

H₀: ρ ≤ 0; H₁: ρ > 0 Reject H₀ if t > 2.5524

3. 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.) The regression equation is: Area =______+_______ Wattage

4. Which heater looks like the “best buy” based on the size of the residual? (Negative value should be indicated by a minus sign. Round residual value to 2 decimal places.)

The______ heater is the "best buy". It heats an area that is square feet larger than estimated by the regression equation.

Answer 1