Deck 14: Sample Size Determination

Question 1

Higher levels of confidence generally require:

A)larger sample sizes.
B)greater variance.
C)smaller sample sizes.
D)smaller standard deviation.

Answer 1

A

Question 2

Which of the following is not a piece of required information in order to determine sample size?

A)estimated population standard deviation
B)estimated population median
C)acceptable level of sampling error
D)All are necessary to determine sample size.
D)desired level of confidence

Answer 2

B

Question 3

About 68% of the area under a standard normal curve covers one _________.

A)mean
B)sample
C)variance
D)standard deviation
E)median

Answer 3

D

Question 4

Which of the following is not a method for estimating the population standard deviation?

A)prior study results
B)conduct a pilot study
C)use secondary data
D)using population size

Question 5

When a research company routinely uses samples of 300 for their studies,they are using which type of plan to determine sample size?

A)the 50% rule
B)budget available
C)rule of thumb
D)number of subgroups to be analyzed

Question 6

____________ is a range of values within which the true population value is estimated to fall.

A)Interval estimate
B)Point estimate
C)Population estimate
D)Sample estimate
E)Universe estimate

Question 7

Which of the following is not a measure of central tendency?

A)variance
B)mean
C)median
D)mode

Question 8

A continuous distribution,which is bell-shaped and symmetric about the mean,is known as:

A)the normal distribution.
B)the chi-square distribution.
C)the F-distribution.
D)the mean distribution.
E)the binomial distribution.

Question 9

If we were making inferences from a single sample,we would expect that there would be a ____ percent probability that the sample mean or proportion generated from our sample results would be within two standard errors of the true population mean.

A)68.26%
B)99.74%
C)97.5%
D)95.44%
E)98.00%

Question 10

All of the statistical methods for determining sample size in this chapter assume which of the following?

A)a large population
B)a valid questionnaire
C)simple random sampling
D)stratified sampling
E)none of these

Question 11

Which of the following would increase the necessary sample size in a study?

A)smaller mean of the variables in question
B)less need for precision
C)need to divide sample into sub-groups
D)larger population
E)smaller population

Question 12

A researcher wants to know the average number of times per month respondents eat at fast food restaurants.The statistic that s/he is most interested in would be the_________.

A)variance
B)mean
C)standard deviation
D)proportion

Question 13

Which of the following is not required to determine sample size using the sample means formula?

A)the standard error of the mean
B)desired level of confidence
C)estimate of population standard deviation
D)level of tolerable error
E)all of these are required.

Question 14

Standard error of the mean is:

A)a measure of dispersion of a large population.
B)a measure of dispersion of large sample.
C)the standard deviation of a distribution of sample means.
D)the error in the computation of population standard deviation.
E)none of these

Question 15

Which of the following is not a determinant of sample size for probability samples?

A)budget available
B)research objectives
C)rule of thumb
D)all of these are determinants

Question 16

How many respondents should be in each important subgroup of a sample?

A)10
B)25
C)50
D)95
E)100

Question 17

Which of the following statements about sample size is false?

A)There is no direct relationship between population size and the size of the
Sample required to estimate population parameters.
B)The larger the sample variance, the larger the sample size that is required.
C)The higher the level of confidence, the larger the sample size that is required.
D)The larger the population, the larger the sample size that is required.
E)All of these statements are false.

Question 18

As the level of tolerable error increases in the sample means formula,the sample size required to represent a particular population is:

A)smaller
B)larger
C)about the same
D)none of these

Question 19

The idea that a large number of sample means or proportions will approximate a normal distribution,regardless of the distribution of the population from which they were drawn,is known as:

A)sample variance
B)population variance
C)central limit theorem
D)random error
E)simple random sample

Question 20

Holding constant at a 95% level of confidence,if the standard deviation increases,then the sample size required to represent the population in question will be _______.

A)larger
B)about the same
C)smaller
D)not applicable

Question 21

When a researcher is not sure if people who responded to the survey are different from those who did not respond,this brings into question the issue of:

A)inappropriate sample size.
B)systematic bias.
C)nonresponse bias.
D)refusal bias.

Question 22

The level of tolerable error (e)in the sample proportions formula is expressed in terms of a percent.

Question 23

___________ sampling error is the amount of sampling error the researcher is willing to accept.

A)Given
B)Projected
C)Accepted
D)Allowable
E)Tolerable

Question 24

The _____________ includes all the possible individuals or objects from whom or about which information is needed to meet the objectives of the research.

A)Group
B)Selection
C)Population
D)Range

E)Variance

Question 25

If a researcher takes enough samples,the data will begin to approach a normal distribution.

Question 26

If large enough samples are taken,most human behavior can be plotted using a normal distribution curve.

Question 27

The results of a sample can be used to generate which of the following concerning the population mean?

A)point estimate
B)interval estimate
C)dot estimate
D)point and interval estimate
E)interval and dot estimate

Question 28

The greater the number of subgroups to be analyzed,the smaller the necessary sample size.

Question 29

A(n)____________ normal distribution is a normal distribution with a mean of zero and a standard deviation of one.

A)Balanced
B)Standard
C)Stock
D)Ordinary
E)Outstanding

Question 30

A confidence interval always includes the true population value.

Question 31

Statistical power is the probability of not making which of the following types of error?

A)Type I
B)Type II
C)Type III
D)Type A
E)Type B

Question 32

Some normal distributions cannot be transformed into standard normal distributions.

Question 33

In a normal distribution,the mean,median,and mode are equal.

Question 34

A range of values with which the true population value is estimated to fall is known as the point estimate.

Question 35

Subgroups are often chosen based on demographics of the sample,such as gender,income,etc.

Question 36

Population size is the most important determinant of effective sample size.

Question 37

A normal distribution has a total of 6 standard deviations.

Question 38

Budget is rarely a consideration when determining sample size.

Question 39

Theoretically,the sampling distribution of the mean is always normally distributed.

Question 40

A type I error is described as which of the following?

A)the error of saying that there is no difference when there is a difference
B)the error of saying that there is a difference when there is not a difference
C)the error of saying that two variables are the same
D)the error of incorrect standard deviation
E)none of these

Question 41

Online interviewing and Internet panels,along with social-media-driven sampling,have had no impact concerning feasible sample sizes.

Question 42

A researcher is conferring with a client to do a telephone interview for a particular topic,which the researcher will subcontract to a field services firm for $10 per usable response.The researcher's client wants to be 95.44% confident of the results.Assume the sample proportions formula is appropriate,and that the level of tolerable sample error is 4%.The budget for data collection only offered by the client can be up to but not over $10,000.How many usable responses are needed for the given level of confidence and much will the subcontractor charge the market researcher for sampling? Is the budget for data collection large enough?

Question 43

Assuming the research objectives of the study can be accomplished,researchers would much prefer to estimate the required sample size using the sample proportion formula rather than the sample means formula.Why?

Question 44

The "budget available" approach forces the researcher to explore alternative data-collection approaches and to carefully consider the value of information in relation to cost.

Question 45

The confidence level is the probability that a particular interval will include true population value.

Question 46

A researcher wants to estimate a population mean.The level of tolerable sampling error is 0.2 of a purchase occasion,with a confidence level of 95.44%.If the estimated population variance is 5 for the most important question in the study,what is the desired sample size?

Question 47

In addition to being interested in estimating sampling means,marketing researchers frequently are interested in estimating proportions or percentages.

Question 48

The proportional property of a normal distribution provides the basis for the statistical inferences.

Question 49

Regardless of how the target sample size is determined,the researcher is confronted with the practical problem of figuring out how many sampling units will be required to complete the assignment.

Question 50

A researcher wants to estimate the percentage of all adults that have used the Internet to seek pre-purchase information in the past 30 days,with a tolerable sampling error (E)of 0.03 and a confidence level of 97.5%.If secondary data indicated that 25% of all adults had used the Internet for such a purpose,what is the sample size?

Question 51

Discuss and give examples of three methods that are used in marketing research for determining sample size.

Question 52

Statistical power is the probability of making a type II error.

Question 53

A sample distribution is a frequency distribution of all the elements of an individual (single)population.

Question 54

The total area under a normal curve is not equal to one,meaning all observations.

Question 55

A particular normal distribution is not uniquely defined by its mean and standard deviation.

Question 56

The finite population correction factor (FPC)is an adjustment to the required sample size that is made in cases where the sample is expected to be equal to 5 percent or more of the total population.

Question 57

Compute the required sample size given the required confidence in the sample results is 90%.The level of tolerable sampling error is 1% and the estimated population standard deviation is 5.

Question 58

The normal distribution is bell-shaped and has only one mode.