In: Statistics and Probability
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:
She randomly collects online listings for 50 single-family homes. .
Requirements and associated point values:
Part 1 – Provide summary statistics (with Excel Data Analysis) by calculating the mean and standard deviation on the asking price, square footage, the number of bedrooms, the number of bathrooms, and the lot size. Explain each factor’s mean and standard deviation. What does each of these summary statistics tell us.
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 |
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Regression Statistics |
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Multiple R |
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R Square |
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Adj. R Square |
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Standard Error |
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Observations |
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ANOVA |
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Df |
SS |
MS |
F |
Significance F |
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Regression |
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Residual |
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Total |
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Coefficients |
Standard Error |
t Stat |
P-value |
Lower 95% |
Upper 95% |
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Intercept |
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SQFT |
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Bed |
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Bath |
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LTSZ |
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Also provide the estimate model equation: Price =
part 1 )
Price | SQFT | Bed | Bath | LTSZ | |
Mean | 208789.320 | 2.598 | 3.560 | 2.490 | 0.818 |
Standard Deviation | 79636.520 | 1.016 | 0.675 | 0.746 | 1.375 |
mean and standard deviation on each variable is above
you can generate by data-> data analysis -> descriptive statistics
check on summary statistics
for each variable
The statistical mean refers to the mean or average that is used to derive the central tendency of the data in question. It is determined by adding all the data points in a population and then dividing the total by the number of points.We derive the average and call as mean.
The standard deviation of a dataset gives you a measure of how spread out it is. On an average, it helps you ascertain how close each point is from the mean
for example average price is 208789.320
and sd of price is 79636.520
part 2)
using data -> data analysis -> regression
SUMMARY OUTPUT | |||||
Regression Statistics | |||||
Multiple R | 0.91940202 | ||||
R Square | 0.845300074 | ||||
Adjusted R Square | 0.83154897 | ||||
Standard Error | 32685.04673 | ||||
Observations | 50 | ||||
ANOVA | |||||
df | SS | MS | F | Significance F | |
Regression | 4 | 262682738715.9840 | 65670684678.9961 | 61.4714 | 0.0000 |
Residual | 45 | 48074052582.8958 | 1068312279.6199 | ||
Total | 49 | 310756791298.8800 | |||
Coefficients | Standard Error | t Stat | P-value | Lower 95% | |
Intercept | 23714.6259 | 25435.2663 | 0.9324 | 0.3561 | -27514.6301 |
SQFT | 44971.6764 | 6262.3653 | 7.1813 | 0.0000 | 32358.6252 |
Bed | -5028.7156 | 7921.0849 | -0.6349 | 0.5287 | -20982.5995 |
Bath | 26142.4324 | 8917.5724 | 2.9316 | 0.0053 | 8181.5196 |
LTSZ | 25725.1240 | 3437.0852 | 7.4846 | 0.0000 | 18802.4790 |