Question 1

In the formula $\bar { x } \pm z _ { d 2 } \sigma / \sqrt { n }$ , the subscript $\alpha / 2$ refers to the area in the lower tail or upper tail of the sampling distribution of the sample mean.

Accepted Answer

A) True 
 B)False

Question 2

What is the margin of error for a 99% confidence interval for the population proportion of people that own more than one mobile phone, if a random sample of 50 people was taken, and 10 of these had more than one mobile phone?

Accepted Answer

2.576 × 0....

Question 3

The width of a confidence interval increases as the level of significance increases.

Accepted Answer

A) True 
 B)False

Question 4

The sample proportion is a biased estimator of the population proportion.

Accepted Answer

A) True 
 B)False

Question 5

A marketing researcher wishes to determine the sample size needed to estimate the proportion of wine drinkers who prefer a certain brand of wine. How many wine drinkers should be surveyed if the researcher wants to be within 0.025 with 95% confidence?

Accepted Answer

The answer of A marketing researcher wishes to determine the...

Question 6

The z value for a 95% confidence interval estimate is:

Accepted Answer

A)   2.12.
B)   1.82.
C)   2.00.
D)   1.96.

Question 7

Which of the following best describes an unbiased estimator?

Accepted Answer

A)   Every estimator is an unbiased estimator.
B)   An interval estimator is an unbiased estimator.
C)   An unbiased estimator of a population parameter is an estimator whose expected value is equal to that parameter.
D)   None of these choices are correct.

Exam 11: Estimation: Describing a Single Population

The width of a confidence interval increases as the level of significance increases.

Correct Answer
verified

The sample proportion is a biased estimator of the population proportion.

Correct Answer
verified

In the formula $\bar { x } \pm z _ { d 2 } \sigma / \sqrt { n }$ , the subscript $\alpha / 2$ refers to the area in the lower tail or upper tail of the sampling distribution of the sample mean.

Correct Answer
verified

What is the margin of error for a 99% confidence interval for the population proportion of people that own more than one mobile phone, if a random sample of 50 people was taken, and 10 of these had more than one mobile phone?

Correct Answer
verified
2.576 × 0....
View Answer

The z value for a 95% confidence interval estimate is:

Correct Answer
verified

Which of the following best describes an unbiased estimator?

Correct Answer
verified

A marketing researcher wishes to determine the sample size needed to estimate the proportion of wine drinkers who prefer a certain brand of wine. How many wine drinkers should be surveyed if the researcher wants to be within 0.025 with 95% confidence?

Correct Answer
verified

Exam 11: Estimation: Describing a Single Population

The width of a confidence interval increases as the level of significance increases.

Correct AnswerverifiedShow Answer

The sample proportion is a biased estimator of the population proportion.

Correct AnswerverifiedShow Answer

In the formula xˉ±zd2σ/n\bar { x } \pm z _ { d 2 } \sigma / \sqrt { n }xˉ±zd2​σ/n​ , the subscript α/2\alpha / 2α/2 refers to the area in the lower tail or upper tail of the sampling distribution of the sample mean.

Correct AnswerverifiedShow Answer

What is the margin of error for a 99% confidence interval for the population proportion of people that own more than one mobile phone, if a random sample of 50 people was taken, and 10 of these had more than one mobile phone?

Correct Answerverified2.576 × 0....View AnswerShow Answer

The z value for a 95% confidence interval estimate is:

Correct AnswerverifiedShow Answer

Which of the following best describes an unbiased estimator?

Correct AnswerverifiedShow Answer

A marketing researcher wishes to determine the sample size needed to estimate the proportion of wine drinkers who prefer a certain brand of wine. How many wine drinkers should be surveyed if the researcher wants to be within 0.025 with 95% confidence?

Correct AnswerverifiedShow Answer

Correct Answer
verified

Correct Answer
verified

In the formula $\bar { x } \pm z _ { d 2 } \sigma / \sqrt { n }$ , the subscript $\alpha / 2$ refers to the area in the lower tail or upper tail of the sampling distribution of the sample mean.

Correct Answer
verified

Correct Answer
verified
2.576 × 0....
View Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified