Question 1

Use the formula   , where   = to calculate the 99% confidence interval for a sample of N = 15 with a mean   = 7.50 and standard deviation (s) = 1.25.

Accepted Answer

A)  99% CI = 7.50 ± .69 
B)  99% CI = 7.50 ± .56 
C)  99% CI = 7.50 ± .95 
D)  99% CI = 7.50 ± 3.30 
A)  99% CI = 7.50 ± .69 
B)  99% CI = 7.50 ± .56 
C)  99% CI = 7.50 ± .95 
D)  99% CI = 7.50 ± 3.30

Question 2

The ______ the desired level of confidence, the ______ the confidence interval for the mean.

Accepted Answer

A)  higher; wider 
B)  lower; narrower 
C)  higher; narrower 
D)  lower; wider 
A)  higher; wider 
B)  lower; narrower 
C)  higher; narrower 
D)  lower; wider

Question 3

Calculate the lower and upper limits of the 95% confidence interval for a sample of N = 25 with a mean   = 4.06 and standard error of the mean   = .27.

Accepted Answer

A)  (3.50, 4.62) 
B)  (3.60, 4.52) 
C)  (3.30, 4.82) 
D)  (1.73, 6.39) 
A)  (3.50, 4.62) 
B)  (3.60, 4.52) 
C)  (3.30, 4.82) 
D)  (1.73, 6.39)

Question 4

When a researcher moves from a 95% confidence level to a 90% confidence level, the confidence interval for the mean becomes ______.

Accepted Answer

A)  wider 
B)  normally distributed 
C)  statistically significant 
D)  narrower 
A)  wider 
B)  normally distributed 
C)  statistically significant 
D)  narrower

Question 5

Calculate the lower and upper limits of the 99% confidence interval for a sample of N = 24 with a mean   = 96.55 and standard error of the mean   = 1.54.

Accepted Answer

A)  (93.36, 99.74) 
B)  (93.91, 99.19) 
C)  (92.23, 100.87) 
D)  (90.20, 102.90) 
A)  (93.36, 99.74) 
B)  (93.91, 99.19) 
C)  (92.23, 100.87) 
D)  (90.20, 102.90)

Question 6

Calculate the lower and upper limits of the 95% confidence interval for a sample of N = 24 with a mean   = 102.97 and standard error of the mean   = 1.85.

Accepted Answer

A)  (99.14, 106.80) 
B)  (99.8, 106.14) 
C)  (97.78, 108.16) 
D)  (99.05, 106.89) 
A)  (99.14, 106.80) 
B)  (99.8, 106.14) 
C)  (97.78, 108.16) 
D)  (99.05, 106.89)

Question 7

The ______ the sample, the more confidence a researcher has that the sample mean estimates the unknown population mean μ, and the ______ the confidence interval around the sample mean.

Accepted Answer

A)  larger; larger 
B)  smaller; smaller 
C)  smaller; larger 
D)  larger; smaller 
A)  larger; larger 
B)  smaller; smaller 
C)  smaller; larger 
D)  larger; smaller

Question 8

Calculate the 95% confidence interval for a sample of N = 30 with a mean   = 249.60 and a population standard deviation (σ) = 50.00.

Accepted Answer

A)  95% CI = 249.60 ± 23.56 
B)  95% CI = 249.60 ± 15.06 
C)  95% CI = 249.60 ± 17.89 
D)  95% CI = 249.60 ± 11.09 
A)  95% CI = 249.60 ± 23.56 
B)  95% CI = 249.60 ± 15.06 
C)  95% CI = 249.60 ± 17.89 
D)  95% CI = 249.60 ± 11.09

Question 9

Calculate the 99% confidence interval for a sample of N = 19 with a mean   = 27.18 and standard deviation (s) = 10.31.

Accepted Answer

A)  99% CI = 27.18 ± 4.98 
B)  99% CI = 27.18 ± 4.11 
C)  99% CI = 27.18 ± 6.82 
D)  99% CI = 27.18 ± 5.25 
A)  99% CI = 27.18 ± 4.98 
B)  99% CI = 27.18 ± 4.11 
C)  99% CI = 27.18 ± 6.82 
D)  99% CI = 27.18 ± 5.25

Question 10

If a researcher chooses a confidence level greater than the 95%, which of the following will occur?

Accepted Answer

A)  a smaller confidence interval that contains the population mean 
B)  a larger confidence interval that contain the population mean 
C)  a loss of precision in estimating the sample mean 
D)  a loss of precision in estimating the population mean 
A)  a smaller confidence interval that contains the population mean 
B)  a larger confidence interval that contain the population mean 
C)  a loss of precision in estimating the sample mean 
D)  a loss of precision in estimating the population mean

Question 11

Which of the following is a reason to retain hypothesis testing?

Accepted Answer

A)  In complex research situations, it may not be possible to do interval estimation. 
B)  Calculating confidence intervals is too complicated. 
C)  Researchers cannot agree as to what is the appropriate level of confidence. 
D)  In simple research situations, confidence intervals would not be reliable. 
A)  In complex research situations, it may not be possible to do interval estimation. 
B)  Calculating confidence intervals is too complicated. 
C)  Researchers cannot agree as to what is the appropriate level of confidence. 
D)  In simple research situations, confidence intervals would not be reliable.

Question 12

Calculate the 90% confidence interval for a sample of N = 25 with a mean   = 2.75 and standard deviation (s) = .93.

Accepted Answer

A)  90% CI = 2.75 ± .33 
B)  90% CI = 2.75 ± .53 
C)  90% CI = 2.75 ± 1.90 
D)  90% CI = 2.75 ± .39 
A)  90% CI = 2.75 ± .33 
B)  90% CI = 2.75 ± .53 
C)  90% CI = 2.75 ± 1.90 
D)  90% CI = 2.75 ± .39

Question 13

Researchers have suggested that hypothesis testing be replaced with or supplemented by ______.

Accepted Answer

A)  interval estimation 
B)  descriptive statistics 
C)  qualitative research 
D)  bivariate analysis 
A)  interval estimation 
B)  descriptive statistics 
C)  qualitative research 
D)  bivariate analysis

Question 14

Calculate the 95% confidence interval for a sample with a mean   = 117.52 and a population standard error of the mean   = 5.57.

Accepted Answer

A)  95% CI = 117.52 ± 10.92 
B)  95% CI = 117.52 ± 9.19 
C)  95% CI = 117.52 ± 14.37 
D)  95% CI = 117.52 ± 7.53 
A)  95% CI = 117.52 ± 10.92 
B)  95% CI = 117.52 ± 9.19 
C)  95% CI = 117.52 ± 14.37 
D)  95% CI = 117.52 ± 7.53

Question 15

The distribution of sample means for larger samples is more closely clustered around the population mean, with less ______ among sample means.

Accepted Answer

A)  confidence 
B)  significance 
C)  similarity 
D)  variability 
A)  confidence 
B)  significance 
C)  similarity 
D)  variability

Question 16

The larger the sample size, the wider the confidence interval for the mean.

Accepted Answer

A) True 
 B)False

Question 17

Calculate the 90% confidence interval for a sample of N = 29 with a mean   = 137.98 and standard error of the mean   = 4.98.

Accepted Answer

A)  90% CI = 137.98 ± 8.47 
B)  90% CI = 137.98 ± 13.76 
C)  90% CI = 137.98 ± 6.68 
D)  90% CI = 137.98 ± 10.20 
A)  90% CI = 137.98 ± 8.47 
B)  90% CI = 137.98 ± 13.76 
C)  90% CI = 137.98 ± 6.68 
D)  90% CI = 137.98 ± 10.20

Question 18

For larger sample sizes, the level of confidence has less of an impact on the width of the confidence interval than for smaller sample sizes. This would indicate that there is a trade-off between ______.

Accepted Answer

A)  probability and precision 
B)  confidence levels and confidence intervals 
C)  sample sizes 
D)  upper and lower limits 
A)  probability and precision 
B)  confidence levels and confidence intervals 
C)  sample sizes 
D)  upper and lower limits

Question 19

Calculate the 95% confidence interval for a sample of N = 25 with a mean   = 4.06 and standard deviation (s) = 1.37.

Accepted Answer

A)  95% CI = 4.06 ± .56 
B)  95% CI = 4.06 ± .46 
C)  95% CI = 4.06 ± .76 
D)  95% CI = 4.06 ± 2.33 
A)  95% CI = 4.06 ± .56 
B)  95% CI = 4.06 ± .46 
C)  95% CI = 4.06 ± .76 
D)  95% CI = 4.06 ± 2.33

Question 20

When a researcher chooses the 90% confidence level instead of the 95% confidence level, which of the following would be true for their decision?

Accepted Answer

A)  The width of the confidence interval would be less precise. 
B)  The width of the confidence interval would be the same. 
C)  The width of the confidence interval would be larger. 
D)  The width of the confidence interval would be smaller. 
A)  The width of the confidence interval would be less precise. 
B)  The width of the confidence interval would be the same. 
C)  The width of the confidence interval would be larger. 
D)  The width of the confidence interval would be smaller.

Use the formula , where = to calculate the 99% confidence interval for a sample of N = 15 with a mean = 7.50 and standard deviation (s) = 1.25.

The the desired level of confidence, the the confidence interval for the mean.

Calculate the lower and upper limits of the 95% confidence interval for a sample of N = 25 with a mean = 4.06 and standard error of the mean = .27.

When a researcher moves from a 95% confidence level to a 90% confidence level, the confidence interval for the mean becomes ______.

Calculate the lower and upper limits of the 99% confidence interval for a sample of N = 24 with a mean = 96.55 and standard error of the mean = 1.54.

Calculate the lower and upper limits of the 95% confidence interval for a sample of N = 24 with a mean = 102.97 and standard error of the mean = 1.85.

The the sample, the more confidence a researcher has that the sample mean estimates the unknown population mean μ, and the the confidence interval around the sample mean.

Calculate the 95% confidence interval for a sample of N = 30 with a mean = 249.60 and a population standard deviation (σ) = 50.00.

Calculate the 99% confidence interval for a sample of N = 19 with a mean = 27.18 and standard deviation (s) = 10.31.

If a researcher chooses a confidence level greater than the 95%, which of the following will occur?

Which of the following is a reason to retain hypothesis testing?

Calculate the 90% confidence interval for a sample of N = 25 with a mean = 2.75 and standard deviation (s) = .93.

Researchers have suggested that hypothesis testing be replaced with or supplemented by ______.

Calculate the 95% confidence interval for a sample with a mean = 117.52 and a population standard error of the mean = 5.57.

The distribution of sample means for larger samples is more closely clustered around the population mean, with less ______ among sample means.

The larger the sample size, the wider the confidence interval for the mean.

Calculate the 90% confidence interval for a sample of N = 29 with a mean = 137.98 and standard error of the mean = 4.98.

For larger sample sizes, the level of confidence has less of an impact on the width of the confidence interval than for smaller sample sizes. This would indicate that there is a trade-off between ______.

Calculate the 95% confidence interval for a sample of N = 25 with a mean = 4.06 and standard deviation (s) = 1.37.

When a researcher chooses the 90% confidence level instead of the 95% confidence level, which of the following would be true for their decision?

Introduction to Statistics

Examining Data: Tables and Figures

Measures of Central Tendency

Measures of Variability

Normal Distributions

Probability and Hypothesis Testing

Testing One Sample Mean

Testing the Difference Between Two Means

Errors in Hypothesis Testing, Statistical Power, and Effect Size

One-Way Analysis of Variance Anova

Two-Way Analysis of Variance Anova

Correlation

Linear Regression and Multiple Correlation

Chi-Square

Filters

Exam 8: Estimating the Mean of a Population

Use the formula , where = to calculate the 99% confidence interval for a sample of N = 15 with a mean = 7.50 and standard deviation (s) = 1.25.

The ______ the desired level of confidence, the ______ the confidence interval for the mean.

Calculate the lower and upper limits of the 95% confidence interval for a sample of N = 25 with a mean = 4.06 and standard error of the mean = .27.

When a researcher moves from a 95% confidence level to a 90% confidence level, the confidence interval for the mean becomes ______.

Calculate the lower and upper limits of the 99% confidence interval for a sample of N = 24 with a mean = 96.55 and standard error of the mean = 1.54.

Calculate the lower and upper limits of the 95% confidence interval for a sample of N = 24 with a mean = 102.97 and standard error of the mean = 1.85.

The ______ the sample, the more confidence a researcher has that the sample mean estimates the unknown population mean μ, and the ______ the confidence interval around the sample mean.

Calculate the 95% confidence interval for a sample of N = 30 with a mean = 249.60 and a population standard deviation (σ) = 50.00.

Calculate the 99% confidence interval for a sample of N = 19 with a mean = 27.18 and standard deviation (s) = 10.31.

If a researcher chooses a confidence level greater than the 95%, which of the following will occur?

Which of the following is a reason to retain hypothesis testing?

Calculate the 90% confidence interval for a sample of N = 25 with a mean = 2.75 and standard deviation (s) = .93.

Researchers have suggested that hypothesis testing be replaced with or supplemented by ______.

Calculate the 95% confidence interval for a sample with a mean = 117.52 and a population standard error of the mean = 5.57.

The distribution of sample means for larger samples is more closely clustered around the population mean, with less ______ among sample means.

The larger the sample size, the wider the confidence interval for the mean.

Calculate the 90% confidence interval for a sample of N = 29 with a mean = 137.98 and standard error of the mean = 4.98.

For larger sample sizes, the level of confidence has less of an impact on the width of the confidence interval than for smaller sample sizes. This would indicate that there is a trade-off between ______.

Calculate the 95% confidence interval for a sample of N = 25 with a mean = 4.06 and standard deviation (s) = 1.37.

When a researcher chooses the 90% confidence level instead of the 95% confidence level, which of the following would be true for their decision?

Introduction to Statistics

Examining Data: Tables and Figures

Measures of Central Tendency

Measures of Variability

Normal Distributions

Probability and Hypothesis Testing

Testing One Sample Mean

Testing the Difference Between Two Means

Errors in Hypothesis Testing, Statistical Power, and Effect Size

One-Way Analysis of Variance Anova

Two-Way Analysis of Variance Anova

Correlation

Linear Regression and Multiple Correlation

Chi-Square

Filters

The the desired level of confidence, the the confidence interval for the mean.

The the sample, the more confidence a researcher has that the sample mean estimates the unknown population mean μ, and the the confidence interval around the sample mean.