In a residual plot against x that does NOT suggest we should challenge the assumptions of our regression model, we would expect to see a _____.
A) horizontal band of points centered near 0
B) widening band of points
C) band of points having a slope consistent with that of the regression equation
D) parabolic band of points

Question

Quizplus · Accepted Answer

In a residual plot against x, we want to see a horizontal band of points centered near 0, which suggests that the residuals are randomly distributed around 0 and the assumptions of the regression model are likely met. A widening band of points or a parabolic band of points suggests that the variance of the residuals is not constant, violating the assumption of equal variance. A band of points having a slope consistent with that of the regression equation suggests that there is a linear relationship between the predictor and response variables, but it does not necessarily address the assumptions of the regression model.

In a Residual Plot Against X That Does NOT Suggest