Concept explainers
Matched Problem 2 In 1950, coal was still a major source of fuel for home energy consumption, and the percentage of occupied housing units heated by fuel oil was only 22.1%. Add the data for 1950 to the data for Example 2, and compute the new least squares line and the new estimate for the percentage of occupied housing units heated by fuel oil in the year 1995. Discuss the discrepancy between the two estimates. (As in Example 2. let .x = 0 represent 1960.)
Example 2 Energy Consumption The use of fuel oil for home healing in the United States has declined steadily for several decades. Table 7 lists the percentage of occupied housing units in the United States that were heated by fuel oil for various years between 1960 and 2015. Use the data in the table and linear regression to estimate the percentage of occupied housing units in the United States that were heated by fuel oil in the year 1995.
Table 7 Occupied Housing Units Heated by Fuel Oil
Year | Percent | Year | Percent |
1960 | 32.4 | 1999 | 9.8 |
1070 | 26.0 | 2009 | 7.3 |
1979 | 19.5 | 2015 | 5.1 |
1989 | 13.3 |
Source: U.S. Census Bureau
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Calculus for Business, Economics, Life Sciences, and Social Sciences (14th Edition)
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