Question 1

Which of the following is the most correct method of determining sample size?
A) percentage of population approach
B) all that can be afforded approach
C) all that time will permit approach
D) using the "100" for local study; "1,000" for national study approach
E) the confidence interval approach

Accepted Answer

The confidence interval approach is the most correct method of determining sample size because it takes into account the desired level of precision and confidence in the estimates. It considers factors such as margin of error, confidence level, and variability in the population. The other approaches (percentage of population, affordability, and time constraints) do not take these factors into account and may result in an inadequate or unnecessarily large sample size. The approach of using a fixed number (100 or 1000) also does not consider the specific characteristics of the population or the research question.

Question 2

Which of the following statements is most accurate regarding the relationship between sample size and the sample representativeness?
A) There is a high relationship between the size of a sample and the representativeness of the population from which it is drawn.
B) There is no relation 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 10 percent of the population.
D) Sample size determines representativeness but only if the sample plan is a probability sampling plan.
E) Sample size determines representativeness but only if the sample plan is a nonprobability sampling plan.

Accepted Answer

B

Question 3

Which of the following is the best definition of variability?
A) it is the amount of dispersion in a data set containing interval or nominal data
B) the difference between scores in the present sample and scores in a previous sample
C) the amount of dissimilarity in ordinal data
D) amount of dissimilarity (or similarity) in respondents' answers to a particular question
E) the amount of responses in one respondent's answers to a particular survey question

Accepted Answer

Variability refers to the extent to which data points in a statistical distribution or data set diverge from the average or mean value, indicating the amount of dissimilarity (or similarity) in respondents' answers to a particular question.

Question 4

Which of the following would be defined as the percentage of respondents that qualify for a survey based on criteria such as age, income, and race.
A) demographic incidence
B) geographic incidence
C) demographic occurrence
D) product incidence
E) customer data

Accepted Answer

Demographic incidence refers to the percentage of respondents that qualify for a survey based on criteria such as age, income, and race. This information can be important in determining the representativeness of a survey sample and guiding efforts to ensure diversity and inclusion. Geographic incidence, product incidence, and customer data are not related to this concept. Demographic occurrence is not a commonly used term in market research.

Question 5

Unfortunately, many managers falsely believe that:
A) sample size is related to proper data analysis
B) sample size is related to the representativeness of the sample
C) sample size is determined by computer programs
D) sample size is an irrelevant "statistical" technicality issue
E) sample size is related to the level of accuracy desired

Accepted Answer

Sample size is related to the representativeness of the sample. It is important to have an appropriate sample size in order to accurately represent the population being studied. A smaller sample size may not accurately represent the population, while a larger sample size may provide more accurate results. Therefore, it is important to consider the representativeness of the sample when determining the appropriate sample size for a study.

Question 6

In a study of the U.S. workforce population, a research company interviews 5,000 persons on a street corner in New York. If they decide to increase the sample size to 10,000, they would:
A) increase the sample size and the representativeness of the sample
B) increase both sample accuracy and representativeness of the sample
C) increase only the representativeness
D) decrease the sample accuracy
E) increase the sample size, but the sample would still not be representative of the population

Accepted Answer

The answer of In a study of the U.S. workforce...

Question 7

If you were to graph sample accuracy and sample size, which of the following generalizations would be most accurate?
A) Accuracy is very low, even with small sample sizes of 50 or below.
B) Accuracy constantly increases as sample size increases; a sample of 2,000 is four times more accurate than a sample of 500.
C) With increases in sample size, sample accuracy decreases.
D) We cannot graph sample size and accuracy because we must also include the level of confidence and the variability within the sample data.
E) Accuracy increases rapidly when sample size increases up to about 500 and then levels off.

Accepted Answer

As sample size increases, accuracy generally increases. However, there comes a point where adding more data no longer significantly improves the accuracy, and this usually occurs around 500 samples. Therefore, accuracy increases rapidly up to around 500 samples and then levels off. It is important to note that this generalization assumes the data is representative and the sample is properly collected and analyzed. Additionally, the level of confidence and variability within the sample data should also be considered when interpreting accuracy.

Question 8

If we were to graph the relationship of sample size (x axis)to sample accuracy (y axis), we would notice that:
A) There is a linear relationship between size and accuracy.
B) Accuracy increases quickly, up to about sample size 500, and then accuracy levels off with relatively small gains made even when sample size is increased to as much as 2,000.
C) Accuracy increases quickly, up to about sample size 5,000, and then accuracy levels off with relatively small gains made even when sample size is increased to as much as 200,000.
D) Accuracy increases quickly, up to about sample size 50, and then accuracy levels off with relatively small gains made even when sample size is increased to as much as 100.
E) We cannot graph sample size and accuracy because we must also include the level of confidence and the variability within the sample data.

Accepted Answer

This is known as the Law of Large Numbers, which states that as the sample size increases, the sample mean will get closer to the true population mean, but eventually, the gain in accuracy from increasing sample size becomes minimal. This leveling off occurs around a sample size of 500 for most situations.

Question 9

Consider 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?
A) 90 percent say "Yes" and 10 percent say "No"
B) 80 percent say "Yes" and 20 percent say "No"
C) 70 percent say "Yes" and 30 percent say "No"
D) 60 percent say "Yes" and 40 percent say "No"
E) 55 percent say "Yes" and 45 percent say "No"

Accepted Answer

The set of responses where 55 percent say "Yes" and 45 percent say "No" shows the most variability because it has the smallest margin between the two responses (10 percent difference) compared to the other options. This means that opinions are more evenly split, indicating greater variability in responses.

Question 10

Which of the following is true regarding probability samples?
A) They are as perfect as a census and contain no errors caused by competitors.
B) They will always contain some inaccuracy (sample error).
C) They contain serious mistakes, but can be adjusted by statistical weighting procedures.
D) They are particularly susceptible to nonsampling errors.
E) When they approach large values, say 1,000, they are equivalent to a census.

Accepted Answer

Probability samples, while not perfect, are still considered the most accurate method of sampling. However, they still contain some level of inaccuracy or sample error. The other options are not true regarding probability samples.

Question 11

Sources of error that come from sources other than the sample selection method and sample size are referred to as:
A) serious mistakes
B) nonsampling errors
C) errors caused by competitors
D) errors caused by clients
E) errors caused by statisticians

Accepted Answer

Nonsampling errors refer to errors that arise from sources other than the sample selection method and sample size, such as measurement errors, processing errors, non-response bias, and other sources of bias or variation that can affect the accuracy and representativeness of the data. While these errors can be serious and may affect the validity of the analysis, they are not caused by factors such as competitors, clients, or statisticians.

Question 12

Which of the following is NOT a component needed for SSI's Formula for determining how many telephone numbers are needed?
A) incidence rate
B) completion rate
C) working phone rate
D) completed interviews required
E) number of qualified interviewers

Accepted Answer

The Formula for determining how many telephone numbers are needed by SSI includes the incidence rate, completion rate, working phone rate, and completed interviews required. The number of qualified interviewers is not a component of this formula.

Question 13

Which of the following is NOT one of the axioms of sample size and accuracy?
A) The only perfectly accurate sample is a census.
B) A probability sample will always have some inaccuracy (sample error).
C) Increasing sample size increases the sample's representativeness.
D) A probability sample size can be a very tiny percentage of the population size and still be very accurate.
E) The size of a probability sample depends on the client's desired accuracy balanced against the cost of data collection.

Accepted Answer

The answer of Which of the following is NOT one...

Question 14

Which of the following is true with regard to variability?
A) p is always less than q
B) q is always less than p
C) q=100%-p
D) p and q are always equal
E) p+q=1.96

Accepted Answer

Variability, also known as the variance, refers to the spread of data in a distribution. It is measured as the percentage of data that falls within a certain range, often defined by standard deviations from the mean. The percentage represented by data points outside of this range is equal to q, while the percentage within the range is equal to p. Therefore, q=100%-p.

Question 15

The sample size determines:
A) representativeness
B) accuracy
C) representativeness and accuracy
D) the population statistic value
E) the mean generated from the sample statistic

Accepted Answer

The answer of The sample size determines:
A) representativeness
B) accuracy
C) representativeness...

Question 16

When all other factors are held constant, as we increase the level of accuracy, the sample size and the cost of a marketing research survey are best characterized by which of the following?
A) sample size will increase but the cost will decrease
B) sample size will decrease but the cost will increase
C) sample size and the cost of the survey will increase
D) the sample size will remain the same but the cost will increase
E) the sample size will decrease but the cost will remain the same

Accepted Answer

When the level of accuracy is increased, the sample size must also increase to achieve a representative sample. This increases the overall cost of the survey as more participants must be recruited, compensated, and processed. Therefore, both the sample size and the cost of the survey will increase when the level of accuracy is increased.

Question 17

One of the reasons why a marketing practitioner should have a basic understanding of sample size determination is because:
A) many practitioners have a false belief that sample size doesn't determine a sample's representativeness
B) it helps managers to manage their resources better
C) a marketing manager should understand that a sample's representativeness is not related to its accuracy
D) the size of the sample is never a major cost factor
E) managers always have a "small sample bias"; they believe small samples are more accurate

Accepted Answer

The answer of One of the reasons why a marketing...

Question 18

Which of the following is true regarding a probability sample?
A) The larger the sample size, the more likely the sample is representative.
B) The larger the sample size, the more accurate it is (less sample error).
C) The more representative the sample, the larger the sample size.
D) They only become accurate when they are larger than 1,000.
E) The larger the sample size, the more room there is for inaccuracy.

Accepted Answer

The larger the sample size, the more accurate it is (less sample error). This is because a larger sample size reduces the sampling error, which is the difference between the sample mean and the population mean.

Question 19

If we know the level of confidence (1.96 for 95 percent), variability estimates, and the size of a sample, there is a formula that allows us to determine:
A) the costs of the sample
B) the size of the sample
C) the representativeness of the sample
D) p or q
E) the accuracy (sample error)

Accepted Answer

The answer of If we know the level of confidence...

Question 20

Sample accuracy refers to:
A) the extent to which the sample is validated
B) the extent to which the sample statistics differ from the true population values the statistics represent
C) the extent to which the population statistics differs from the representativeness of the sample
D) a statistical concept that can be assessed only theoretically
E) how close the sample statistics match the predetermined values expected by management

Accepted Answer

Sample accuracy is the extent to which the sample statistics differ from the true population values they represent. It is a measure of how well the sample represents the population from which it was selected.

Quiz 13: Determining the Size of a Sample

Which of the following is the most correct method of determining sample size?

Which of the following statements is most accurate regarding the relationship between sample size and the sample representativeness?

Which of the following is the best definition of variability?

Which of the following would be defined as the percentage of respondents that qualify for a survey based on criteria such as age, income, and race.

Unfortunately, many managers falsely believe that:

In a study of the U.S. workforce population, a research company interviews 5,000 persons on a street corner in New York. If they decide to increase the sample size to 10,000, they would:

If you were to graph sample accuracy and sample size, which of the following generalizations would be most accurate?

If we were to graph the relationship of sample size (x axis) to sample accuracy (y axis) , we would notice that:

Consider 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?

Which of the following is true regarding probability samples?

Sources of error that come from sources other than the sample selection method and sample size are referred to as:

Which of the following is NOT a component needed for SSI's Formula for determining how many telephone numbers are needed?

Which of the following is NOT one of the axioms of sample size and accuracy?

Which of the following is true with regard to variability?

The sample size determines:

When all other factors are held constant, as we increase the level of accuracy, the sample size and the cost of a marketing research survey are best characterized by which of the following?

One of the reasons why a marketing practitioner should have a basic understanding of sample size determination is because:

Which of the following is true regarding a probability sample?

If we know the level of confidence (1.96 for 95 percent) , variability estimates, and the size of a sample, there is a formula that allows us to determine:

Sample accuracy refers to: