Chapter 19, Problem 7E

(a)

To determine

To explain which statement is true.

Answer to Problem 7E

False.

Explanation of Solution

It is given that several factors are involved in the creation of a confidence interval. Among the mare the sample size, the level of confidence and the margin of error. Thus, we have that for a given sample size higher confidence interval means a smaller margin of error. This statement is false because a larger sample size always reduces variability and allows for greater confidence.

(b)

To determine

To explain which statement is true.

Answer to Problem 7E

True.

Explanation of Solution

It is given that several factors are involved in the creation of a confidence interval. Among the mare the sample size, the level of confidence and the margin of error. Thus, we have that for a specified confidence level larger samples provide smaller margin of error. This statement is true because a larger sample size always reduces variability and allows for greater confidence.

(c)

To determine

To explain which statement is true.

Answer to Problem 7E

True.

Explanation of Solution

It is given that several factors are involved in the creation of a confidence interval. Among the mare the sample size, the level of confidence and the margin of error. Thus, we have that for a fixed margin of error, larger samples provide greater confidence. This statement is true because a larger sample size always reduces variability and allows for greater confidence.

(d)

To determine

To explain which statement is true.

Answer to Problem 7E

False.

Explanation of Solution

It is given that several factors are involved in the creation of a confidence interval. Among the mare the sample size, the level of confidence and the margin of error. Thus, we have that for a given confidence level, having the margin of error requires a sample twice as large. This statement is false because a larger sample size always reduces variability and allows for greater confidence.