The relationship between energy consumption and household income was studied, yielding the following data on household income X (in units of $1,000/year) and energy consumption Y (in units of 108 Btu/year). Energy Cons. (y) HH Income )x)
1.8 20.0
3.0 30.5
4.8 40.0
5.0 55.1
6.5 60.3
7.0 74.9
9.0 88.4
9.1 95.2
a) Plot a scattergram of these data
b) Estimate the linear regression equation ? Y/x = ?0 + ?? x.
c) If x = 50 (household income of $50,000), estimate the average energy consumed for households of this income. What would your estimate be for a single household?
d) How much would you expect the change in consumption to be if any household income increases $2000/year?