Quantitative Methods PSY302 Quiz Chapter Six

Confidence Intervals

1. We calculate the sample mean in order to:

A. practice with Excel

B. prove the null hypothesis

C. create sampling error

D. decrease confirmation bias

E. estimate the population mean

1. We calculate the sample mean in order to:

A. practice with Excel

B. prove the null hypothesis

C. create sampling error

D. decrease confirmation bias

E. estimate the population mean

2. A range of valueswithin which the true mean of the population is

believed to exist is called a. (105)

A. standard deviation

B. non random sample

C. research design or meta-analysis

D. frequency distribution

E. confidence interval

2. A range of valueswithin which the true mean of the population is

believed to exist is called a. (105)

A. standard deviation

B. non random sample

C. research design or meta-analysis

D. frequency distribution

E. confidence interval

3. The Z score for a 95% confidence interval is: (107)

A. 2.58

B. -1.11

C. 1.96

D. .002

E. .5

3. The Z score for a 95% confidence interval is: (107)

A. 2.58

B. -1.11

C. 1.96

D. .002

E. .5

4. In the sampling distribution of means shown below what is on the X axis?

A. frequency

B. raw score

C. the variance

D. the mean

E. all of the above

4. In the sampling distribution of means shown below what is on the X axis?

A. frequency

B. raw score

C. the variance

D. the mean

E. all of the above

5. I have an estimate based on a mean of 50 with a margin of error of 10. What would be the upper

limit of my confidence interval?

A. 35

B. 60

C. 55

D. 40

E. 50

5. I have an estimate based on a mean of 50 with a margin of error of 10. What would be the upper

limit of my confidence interval?

A. 35

B. 60

C. 55

D. 40

E. 50

6. For a 95% confidence interval, the formula for the margin of error is the Z-score (i.e. 1.96) times:

A. μ

B. .95

C. the standard error

D. sample mean

E. population mean

6. For a 95% confidence interval, the formula for the margin of error is the Z-score (i.e. 1.96) times:

A. μ

B. .95

C. the standard error

D. sample mean

E. population mean

7. As n increases the standard error: (111)

A. remains the same

B. increases

C. decreases

D. doubles

E. turns to zero

7. As n increases the standard error: (111)

A. remains the same

B. increases

C. decreases

D. doubles

E. turns to zero

8. When you divided the standard deviation of the population by the square root of n (the sample

size) you have the:

A. standard error

B. mean

C. correlation coefficient

D. confidence interval

E. sum of squares

8. When you divided the standard deviation of the population by the square root of n (the sample

size) you have the:

A. standard error

B. mean

C. correlation coefficient

D. confidence interval

E. sum of squares

9. A 95% confidence interval is constructed so that it will capture the true mean of the population:

(115)

A. never

B. always

C. 99% of the time

D. 95% of the time

E. On president’s day

The error bars on the figures represent the 95 percent confidence interval.

9. A 95% confidence interval is constructed so that it will capture the true mean of the population:

(115)

A. never

B. always

C. 99% of the time

D. 95% of the time

E. On president’s day

The error bars on the figures represent the 95 percent confidence interval.

10. The X axis of a sampling distribution of the means shows the:

A. value of the mean

B. Z score

C. the number of standard errors above or below the mean

D. all of the above

10. The X axis of a sampling distribution of the means shows the:

A. value of the mean

B. Z score

C. the number of standard errors above or below the mean

D. all of the above

The End

1. e2. e3. c4. d5. b6. c7. c8. a9. d10. d