Chapter 10 Determining the Size of a Sample Flashcards
the false belief that sample size determines a sample’s representativeness.
large sample size bias
The size of a sample has nothing to do with its representativeness. Sample size affects the ___________.
sample accuracy
The _________ is the correct method by which to determine sample size.
confidence interval approach
_________ pertains to all sources of error other than the sample selection method and sample size, including problem specification mistakes, question bias, data recording errors, or incorrect analysis.
Nonsampling error
The only perfectly accurate sample is a _____.
census
The ______ the size of the (probability) sample, the _____ its margin of sample error.
larger
lower
Margin of sample error formula
Margin of Sample Error%=1.96×p×qn
With a sample size of _____ or more, very little gain in accuracy occurs even with doubling or tripling the sample size.
1,000
______ refers to how similar (or dissimilar) responses are to a given question.
Variability
A _____ split in responses signifies maximum variability (dissimilarity) in the population, whereas a _____ split signifies little variability.
50/50
90/10
Sample error formula with p = 50% and q = 50%
±Margin of Sample Error%=1.96×2,500n
A ______ is a range whose endpoints define a certain percentage of the responses to a question.
confidence interval
The theory called the _______ underlies many statistical concepts, and this theory is the basis of the fifth axiom
central limit theorem
A ________ defines endpoints based on knowledge of the area under a bell-shaped curve.
confidence interval
Confidence interval formula
Confidence interval=p±margin of sample error
The _______ gives the range of findings if the survey were replicated many times with the identical sample size.
confidence interval
With few exceptions, the _____ and the _______ are not related to each other.
sample size
size of the population
To compute sample size, only three items are required:
variability, acceptable sample error, and confidence level.
Standard sample size formula
n=z2(pq)e2
The _________ is applicable if you are concerned with the nominally scaled questions in the survey, such as yes or no questions.
standard sample size formula
_________ is represented by the term e, which is the amount of sample error the researcher will permit to be associated with the survey.
Acceptable margin of sample error
In marketing research, a ___ level of confidence is standard practice.
95%
In marketing research, a ___ level of confidence is standard practice.
95%
When estimating a standard deviation, researchers may rely on
a) prior knowledge of the population (previous study); (b) a pilot study; or (c) divide the range by 6.
By estimating p to be other than ___, the researcher can reduce the sample size and save money.
50%
Researchers can estimate variability by
(a) assuming maximum variability (p = 50%, q = 50%), (b) seeking previous studies on the population, or (c) conducting a small pilot study.
Marketing researchers often must help decision makers understand the _________ of their requests for high precision, expressed as acceptable sample error.
sample size implications
Use of _______ level of confidence is standard in sample size determination.
95% or 99%
The researcher must take ____ into consideration when determining sample size.
cost
A table that relates data collection cost and sample error is a useful tool when deciding on the ______.
survey sample size
______ rely on erroneous rules of thumb.
Arbitrary sample size approaches
_________ are simple and easy to apply, but they are neither efficient nor economical.
Arbitrary sample sizes
Using _______ can result in a sample that may be too small or too large.
conventional sample size
________ ignore the special circumstances of the survey at hand.
Conventional sample sizes
, meaning that the researcher wishes to perform a particular type of data analysis that has sample size requirements.
statistical analysis approach
Sometimes the researcher’s desire to use particular statistical techniques influences ______.
sample size
Using _____ as the sole determinant of sample size may seem wise, but it is not.
cost
The appropriateness of using cost as a ______ depends on when cost factors are considered.
basis for sample size
a __________ is one in which the sample exceeds 5% of the total population size.
small population situation
, which is an adjustment factor that is approximately equal to the square root of that proportion of the population not included in the sample.
finite multiplier
With ______, you should use the finite multiplier to determine sample size.
small populations
Small population sample size formula
Small Population Sample Size=sample size formula n×N−nN−1
Appropriate use of the _________ will reduce a calculated sample size and save money when performing research on small populations.
finite multiplier formula
When using ________ sampling, sample size is unrelated to accuracy, so cost–benefit considerations must be used.
nonprobability
