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	1,250		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

a. 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 Wattage and Area is _______.

b. Conduct a test of hypothesis to determine if it is reasonable that the coefficient is greater than zero. Use the 0.05 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 > 1.7341

t=______

C. 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

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

Answer 1