Chapter 21, Problem 22E

(a)

To determine

To explain what is a Type I error.

Explanation of Solution

It is given in the question that production managers on an assembly line must monitor the output to be sure that the level of detective products remains small. They periodically inspect a random sample of the items produced. Thus, in this context, Type I error means that deciding that there has been an increase in defective items when there actually has not.

(b)

To determine

To explain what is a Type II error.

Explanation of Solution

It is given in the question that production managers on an assembly line must monitor the output to be sure that the level of detective products remains small. They periodically inspect a random sample of the items produced. Thus, in this context, Type II error means that deciding that the number of defective items is small when it has actually increased.

(c)

To determine

To find out which type of error would the factory owner consider more serious.

Answer to Problem 22E

Type II error would the factory owner consider more serious.

Explanation of Solution

It is given in the question that production managers on an assembly line must monitor the output to be sure that the level of detective products remains small. They periodically inspect a random sample of the items produced. Thus, Type II error would the factory owner consider more seriousbecause defects found in the factory are much cheaper to fix than defects found after items have already been sold.

(d)

To determine

To find out which type of error might customers consider more serious.

Answer to Problem 22E

Type II error might customers consider more serious.

Explanation of Solution

It is given in the question that production managers on an assembly line must monitor the output to be sure that the level of detective products remains small. They periodically inspect a random sample of the items produced. Thus, Type II error might customers consider more seriousbecause the customers would not want to buy defective items.