Concept explainers
Median Income The following table gives the median household income, meaning that half the households in the United States earned less than that amount and half the households earned more than that amount (see Chapter 10), for various years. (Data from: US. Census Bureau.)
Year | 2005 | 2010 | 2014 | 2015 |
Household Income | $46,326 | $49,276 | $53657 | $56,516 |
a. Use the data from the years 2005 and 2010 to find a linear model for these data, with a: = 5 corresponding to the year 2005.
b. Find the least-squares regression line for all these data.
c. Use the models in parts (a) and (b) to estimate the median household income for the year 2015 to the nearest dollar. Compare the estimates to the actual value for 2015.
d. Assuming the trend continues, use the model for part (b) to estimate the median household income for the year 2018 to the nearest dollar.
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