In: Statistics and Probability
To determine if the amount a family spends on their home depends on their income, a social researcher collects the Median Household Income (in $1,000) and Median Home Prices (in $1,000) for 34 U.S. cities. The data appear in the HomePrice worksheet of the Simple Regression work sheet below..
a) Draw a scatter plot of the data. Does there appear to be a linear association between Household Income and Home Price?
b) Fit the simple linear regression model using Home Price as the dependent or Y variable and Household Income as the dependent or X variable. Is the model significant at = 0.05?
c) What percentage of the variation in Home Price has been explained by the linear relationship with Household Income?
d) Provide the equation of the fit line. Interpret the parameter estimates in the context of the problem.
e) Use a hypothesis test to determine if the increase in house price is less than $4,000 for a $1,000 in household income, i.e., test the hypothesis null hypothesis Beta1 >or= to 4.0 versus the alternative Beta1 < 4.0 using alpha 0.05.
g) Provide a point prediction and a 95% confidence interval for the median house price for cities with a median household income of 100.
City | Income | Home |
Alexandria, VA | 59.976 | 290 |
Bernards Twp., NJ | 112.435 | 279.9 |
Brentwood, TN | 107.866 | 338.25 |
Bridgewater, NJ | 93.484 | 316 |
Cary, NC | 77.091 | 207 |
Centreville, VA | 77.243 | 250 |
Chantilly, VA | 94.864 | 320 |
Chesapeake, VA | 53.758 | 150 |
Collierville, TN | 85.716 | 230 |
Columbia, MD | 77.033 | 199 |
Coral Springs, FL | 62.632 | 218.5 |
Dranesville, VA | 109.502 | 290 |
Dunwoody, GA | 86.971 | 315 |
Ellicott City, MD | 83.583 | 248 |
Franconia, VA | 84.537 | 290 |
Gaithersburg, MD | 64.944 | 220 |
Hoover, AL | 64.431 | 170.45 |
Hunter Mill, VA | 93.987 | 290 |
Lower Makefield Twp., PA | 102.997 | 205 |
Manalapan Twp., NJ | 91.245 | 410 |
Marlboro Twp., NJ | 108.759 | 379.975 |
Matoaca, VA | 65.149 | 135 |
Newtown, CT | 97.723 | 358.5 |
North Andover, MA | 79.169 | 342.5 |
Oakton, VA | 90.824 | 341 |
Olney, MD | 100.716 | 287.45 |
Peachtree City, GA | 79.805 | 214.5 |
Ramapo, NY | 64.954 | 330.875 |
Randolph Twp., NJ | 104.121 | 444.5 |
Reston, VA | 85.264 | 240 |
Roswell, GA | 76.53 | 226.45 |
Sugarland Run, VA | 103.35 | 278.25 |
Sully, VA | 92.942 | 290 |
Wellington, FL | 76.076 | 230 |