Question

(a) What is the average BMI for a woman who averages 9500 steps per day? (b) If an observed BMI at x = 9.5 were 22.8, what is the residual? (c) Suppose that you want to use the estimated population regression line to examine the average BMI for a woman who averages 2000, 7000, 12,000, and 17,000 steps per day. Discuss the appropriateness of using the equation to predict BMI for each of these activity levels.

Answer 1

Answer:

a. 23.3555

b. -0.5555

c. If x is outside of sample data, the estimated regression value is not sufficient.

Explanation:

a. The computation of predicted BMI is shown below:-

Predicted BMI = $b_{o}$ - $b_{1}$ × 9.5

= 29.578 - 0.655 × 9.5

= 23.3555

b. The computation of residual is given below:-

Residual = Actual - Predicted value

= 22.8 - 23.3555

= -0.5555

c. The appropriateness of using a BMI prediction equation for each of these levels of activity is here below:-

If x is outside of sample data, the estimated regression value is not sufficient.