Chapter 11.4, Problem 17E

a.

To determine

Tell whether the following statement, if true would lower your confidence in the result.

Answer to Problem 17E

It will not lower my confidence as this method is the best

Explanation of Solution

Given information :

The question is:

Scientists conducted a study to determine the average height of pine trees in a large forest. They did so by measuring trees from the forest

The statement is “The scientists chose the trees in their sample randomly”

It will not lower my confidence as this method is the best because the scientist selected the samples randomly that why this is lower my confidence.

b.

To determine

Tell whether the following statement, if true would lower your confidence in the result.

Answer to Problem 17E

It will lower my confidence.

Explanation of Solution

Given information :

The question is:

“The scientist selected the trees only from the western portion of forest”

It will lower my confidence because the scientist selected the trees from the western part and as what about the trees in other parts of the forest

c.

To determine

Tell whether the following statement, if true would lower your confidence in the result.

Answer to Problem 17E

This will not lower my confidence as if they are representative

Explanation of Solution

Given information :

The question is:

“Some of the trees measured in the study were much taller than others”

This will not lower my confidence because they measured the height of and if they are representative.

d.

To determine

To state : that the scientist measured only a small fraction of the total number of pine trees in the forest

Answer to Problem 17E

This will lower my confidence as the result may not be corrected

Explanation of Solution

Given information :

The question is:

“The scientist measured only a small fraction of the total number of pine trees in the forest”

This will lower my confidence because as the above statement it measured the height of the trees as the result may not be corrected.