In: Statistics and Probability
GBA 306 Statistical Methods of Business II – Case Study – Indiana Real Estate
Ann Perkins, a realtor in Brownsburg, Indiana, would like to use
estimates from a multiple regression model to help prospective
sellers determine a reasonable asking price for their homes. She
believes that the following four factors influence the asking price
(Price) of a house:
1) The square footage of the house (SQFT)
2) The number of bedrooms (Bed)
3) The number of bathrooms (Bath)
4) The lot size (LTSZ) in acres
She randomly collects online listings for 50 single-family homes.
The data file is located in the Blackboard “Case Study Indiana Real
Estate Data File Excel” within the Case Study folder.
Requirements and associated point values:
.
Part 2 – Estimate and interpret a multiple regression model where
the asking price is the response variable and the other four
factors are the explanatory variables.
The end result should be a Excel Regression Output
SUMMARY OUTPUT
Regression Statistics
Multiple R
R Square
Adj. R Square
Standard Error
Observations
ANOVA
Df SS MS
F Significance F
Regression
Residual
Total
Coefficients Standard
Error t Stat P-value Lower
95% Upper 95%
Intercept
SQFT
Bed
Bath
LTSZ
Also provide the estimate model equation: Price =
A total of 40 points will be assigned to Part 2.
Part 3 – Interpret the resulting coefficient of
determination.
A total of 20 points will be assigned to Part 3.
Price SQFT Bed
Bath LTSZ
399900 5.026 4 4.5
0.3
375000 3.2 4 3
5
372000 3.22 5 3
5
370000 4.927 4 4
0.3
325000 3.904 3 3
1
325000 2.644 3 2.5
5
319500 5.318 3 2.5
2.5
312900 3.144 4 2.5
0.3
299900 2.8 4 3
5
294900 3.804 4 3.5
0.2
269000 3.312 5 3
1
250000 3.373 5 3.5
0.2
249900 3.46 2 2.5
0.6
244994 3.195 4 2.5
0.2
244900 2.914 3 3
0.3
239900 2.881 4 5
0.3
234900 1.772 3 2
3.6
234000 2.248 3 2.5
0.3
229900 3.12 5 2.5
0.2
219900 2.942 4 2.5
0.2
209900 3.332 4 2.5
0.2
209850 3.407 3 2.5
0.3
206900 2.092 3 2
0.3
200000 3.859 4 2
0.2
194900 3.326 4 2.5
0.1
184900 1.874 3 2
0.5
179900 1.892 3 1.5
0.7
179500 2.5 4 2.5
0.5
165000 2.435 4 2.5
0.4
159900 2.714 3 2.5
0.2
159900 1.85 3 2.5
0.5
155000 3.068 4 3.5
0.2
154900 2.484 4 2.5
0.3
152000 1.529 4 2
0.4
149900 2.876 4 2.5
0.2
148500 2.211 4 2.5
0.1
146900 1.571 3 2
0.2
145500 1.503 4 2
0.5
144900 1.656 3 2
0.5
144900 1.521 3 2
0.6
139900 1.315 3 2
0.2
137900 1.706 3 2
0.3
132900 2.121 4 2.5
0.1
129900 1.306 3 2
0.5
129736 1.402 3 2
0.5
125000 1.325 3 2
0.3
119500 1.234 3 2
0.2
110387 1.292 3 1
0.2
106699 1.36 3 1.5
0.1
102900 1.938 3 1
0.1
Part 2 –
The regression output is:
Regression Statistics | ||||||||
Multiple R | 0.919402 | |||||||
R Square | 0.8453 | |||||||
Adjusted R Square | 0.831549 | |||||||
Standard Error | 32685.05 | |||||||
Observations | 50 | |||||||
ANOVA | ||||||||
df | SS | MS | F | Significance F | ||||
Regression | 4 | 2.63E+11 | 6.57E+10 | 61.47143 | 1.16E-17 | |||
Residual | 45 | 4.81E+10 | 1.07E+09 | |||||
Total | 49 | 3.11E+11 | ||||||
Coefficients | Standard Error | t Stat | P-value | Lower 95% | Upper 95% | Lower 95.0% | Upper 95.0% | |
Intercept | 23714.63 | 25435.27 | 0.932352 | 0.35613 | -27514.6 | 74943.88 | -27514.6 | 74943.88 |
SQFT | 44971.68 | 6262.365 | 7.18126 | 5.49E-09 | 32358.63 | 57584.73 | 32358.63 | 57584.73 |
Bed | -5028.72 | 7921.085 | -0.63485 | 0.52874 | -20982.6 | 10925.17 | -20982.6 | 10925.17 |
Bath | 26142.43 | 8917.572 | 2.931564 | 0.005285 | 8181.52 | 44103.35 | 8181.52 | 44103.35 |
LTSZ | 25725.12 | 3437.085 | 7.484576 | 1.96E-09 | 18802.48 | 32647.77 | 18802.48 | 32647.77 |
The multiple regression model is:
Price = 23714.63 + 44971.68SQFT - 5028.72Bed + 26142.43Bath + 25725.12LTSZ
Part 3 –
The resulting coefficient of determination is 0.8453.
84.53% of the variation in price is explained by the model.