For Exercises 7–14, you are given the regression equation.

  1. Calculate the predicted values.
  2. Compute the residuals.
  3. Construct a scatterplot of the residuals versus the predicted values.
  4. Use technology to construct a normal probability plot of the residuals.
  5. Verify that the regression assumptions are valid.

Question 13.9

9.

−5 0
−4 8
−3 8
−2 16
−1 16

13.1.9

(a) and (b)

Predicted value
 Residual
()
–5 0 1.6 –1.6
–4 8 5.6 2.4
–3 8 9.6 –1.6
–2 16 13.6 2.4
–1 16 17.6 –1.6

(c) and (d) See Solutions Manual. (e) The scatterplot of the residuals contains an unhealthy pattern, so the regression assumptions are not verified.