TABLE 17-1
A real estate builder wishes to determine how house size (House)is influenced by family income (Income),family size (Size),and education of the head of household (School).House size is measured in hundreds of square feet,income is measured in thousands of dollars,and education is in years.The builder randomly selected 50 families and ran the multiple regression.Microsoft Excel output is provided below:
-Referring to Table 17-1,what are the residual degrees of freedom that are missing from the output?
A)3
B)46
C)49
D)50

Question

TABLE 17-1
A real estate builder wishes to determine how house size (House)is influenced by family income (Income),family size (Size),and education of the head of household (School).House size is measured in hundreds of square feet,income is measured in thousands of dollars,and education is in years.The builder randomly selected 50 families and ran the multiple regression.Microsoft Excel output is provided below: 
-Referring to Table 17-1,what are the residual degrees of freedom that are missing from the output?
A)3 
B)46 
C)49 
D)50

Quizplus · Accepted Answer

The residual degrees of freedom are equal to the total degrees of freedom minus the number of predictors (including the constant term). In this case, there are 50 total observations and 3 predictors (Income, Size, and School), so the missing residual degrees of freedom are equal to 50-3=47. However, Excel always includes a constant term in the regression, so we need to subtract one more from the residual degrees of freedom to account for that. Therefore, there are a total of 46 residual degrees of freedom missing from the output. Option B is the only choice that correctly represents the missing degrees of freedom.

TABLE 17-1 A Real Estate Builder Wishes to Determine How House Size