Chapter 4.2, Problem 4.33E

To determine

To calculate the residuals for the eight hikers and then find the sum of the eight residuals.

Answer to Problem 4.33E

The sum of all residuals is $0.49$ .

Explanation of Solution

The residual is the difference between the observed $y$ and the predicted $y$ .

Given the regression equation Pack weight $=16.3+0.09(\text{body weight)}$ .

Then the residuals are:

Residual $\text{=}26-(16.3+0.09(120))=-1.1$

Residual $\text{=30}-(16.3+0.09(187))=-3.13$

Residual $\text{=}26-(16.3+0.09(109))=-0.11$

Residual $\text{=}24-(16.3+0.09(103))=-1.57$

Residual $\text{=}29-(16.3+0.09(131))=0.81$

Residual $\text{=35}-(16.3+0.09(165))=3.85$

Residual $\text{=31}-(16.3+0.09(158))=0.48$

Residual $\text{=}28-(16.3+0.09(116))=1.26$

Now we have to add all residuals:

  $\begin{array}{l}-1.1-3.13-0.11-1.57+0.81+3.85+0.48+1.26\\ =0.49\end{array}$