The number of degrees of freedom associated with the standard error of estimate is
A) n-1 since only the slope is estimated from sample data.
B) n-1 since only the intercept is estimated from sample data.
C) n-1 since only the predicted value of y is estimated from sample data.
D) n-2 since the slope and the intercept are estimated from sample data.

Question

Quizplus · Accepted Answer

The standard error of estimate is the standard deviation of the residuals, which are the differences between the observed values of y and the predicted values of y. To estimate the slope and intercept, we use the sample data, which reduces the degrees of freedom by two. Therefore, the number of degrees of freedom associated with the standard error of estimate is n-2.

The Number of Degrees of Freedom Associated with the Standard