The polynomial regression equation is useful when a linear regression equation fails to model the curvature between the response variable and the predictor variables. In order to make the polynomial regression equation easier to handle, a suitable method of transformations can be used on the variables. Also, when there are more complex curvature between the response and the predictor variables then the polynomial regression equations can be used than method of transformations.
Thus, the statement “Polynomial regression equations are useful for modeling more complex curvature in regression equations that can be handled by using the method of transformations.” is ul(True).