Sample size (n) is related to the degree of the confidence (1-alpha) in that the
a. larger the degree of confidence, the larger the sample size.
b. smaller the degree of confidence, he larger the sample size.
c. sample size would be the same irrespective of the degree of confidence.
d. sample size formula is related to z and not to the degree f confidence.
e. None of the above.
Question 2In a study of the U.S. labor force to determine its attitudes and opinions, a research company interviews 5,000 persons on a street corner in Manhattan, NY. In order to get more accurate results, they decide to increase the sample size to 10,000 . Which of the following would be true?
a. Increase the sample size will increase the representativeness of the sample.
b. Increase the sample size would still not increase the representative of the sample.
c. Since a convenient sample was used, sample representativeness is impossible.
d. Both b and c.
e. None of the above is correct.
Question 3If you were to graph precision (H) and sample size (n), which of the following generalizations would be most accurate?
a. Precision is very low with small sample sizes of 50 or below.
b. Precision constantly increases as sample size increases; a sample of 2,000 is four times more precise than a sample of 500.
c. Precision increases rapidly when sample size increases up to about 500 and then begins to level off.
d. Precision and sample size have nothing to do with each other, therefore graphing them make no sense
e. Both b and c are true.
Question 4Consider that we have nominal data (responses are categorical) and the responses are Yes or No to the question: The next time you order pizza, will you use Domino's? Which of the following sets of responses shows the MOST variability (all else being equal)?
a. 90 say Yes and 10 say No
b. 80 say Yes and 20 say No
c. 70 say Yes and 30 say No
d. 60 say Yes and 40 say No
e. 50 say Yes and 50 say No
Question 5In estimating the standard deviation in the population for the formula for calculating the sample size for estimating a mean, we can use some prior knowledge about the
a. sample to estimate our standard deviation.
b. population, undertake a pilot study or estimate the range, and divide by 10.
c. population, undertake a pilot study or estimate the range, and divide by 6.
d. Either of the two; b or c would work.
e. None of the above; if you do not have the actual standard deviation, you cannot use the formula.
Question 6Which of the following statements is most accurate regarding the relationship between sample size and the sample representativeness?
a. There is no relation between the size of a sample and the representativeness of the population from which it is drawn.
b. There is a strong positive relationship between the size of a sample and the representativeness of the population from which it is drawn.
c. You cannot have a representative sample unless the sample size is equal to or exceeds ten percent of the population.
d. Sample size determines representativeness but only if the sample plan is a probability sampling plan.
e. None of the above.
Question 7A researcher was conducting an investigation to determine if level of education affected a person's consumption of alcoholic beverages. The researcher was specifically interested in determining whether those with a grade school, high school, or college education were more likely to drink beer, wine, or hard liquor. To investigate the question the researcher planned to cross classify these three education levels of respondents against their preferences for each of these beverages. She estimated that 20 percent of the population of interest had a college education, 70 percent a high school education, and 10 percent only a grade school education, and further that 40 percent of the population preferred beer, 40 percent wine, and 20 percent hard liquor. She desired a minimum of 20 observations per cell on which to base percentages. How large a sample should she select?
a. 200
b. 250
c. 400
d. 500
e. 100
Question 8When using anticipated cross classifications to determine sample size, the general rule of thumb suggests using at least __________ units in major breakdowns and __________ units in minor breakdowns.
a. 150, 20 to 50
b. 50, 10 to 20
c. 75, 100
d. 200, 75
e. 100, 20 to 50
Question 9A researcher has estimated that she needs a sample of size n=100 from a population consisting of 1,000 elements. Recognizing that the sample represents 10 of the population, she decides to apply the finite population correction factor to her initial estimate. What is the corrected sample size?
a. 10
b. 84
c. 105
d. 91
e. 95
Question 10The finite population correction factor
a. is used when the sample size is larger than 5 percent of the population.
b. reduces the estimate of the standard error.
c. can be used to decrease the costs of a study.
d. Both a and b.
e. a, b, and c.
Quick Reply
