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: ρ ≤
0; H1: ρ > 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.)
