Chapter 5.2, Problem 5.32E

(a)

To determine

To explain why it wouldn’t be practical for scientists to obtain an SRS in this setting.

Explanation of Solution

It wouldn’t be practical for scientists to obtain an SRS in this setting because the sample is too large and conducting a fair and appropriate SRS would be too time-consuming and costly.

(b)

To determine

To explain why the sampling method given in the question biased.

Explanation of Solution

This is biased because it does not give every tree an equal opportunity of being sampled since only the trees on the border are being sampled and the trees on the interior are left out.

(c)

To determine

To identify can scientists conclude that $35\%$ of all pine trees on the west side of the park are infested and explain why or why not.

Answer to Problem 5.32E

No.

Explanation of Solution

  $35\%$ of all pine trees on the west side of the park are not infested as the sampling gives an estimate, or an average, but not an exact percentage of infested trees. For example, more trees on the outside may be infested on the border than on the interior or vice versa.