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MMC 3420 EXAM 2 Questions and Correct
Answers/ Latest Update / Already Graded
Distinguish between a population and a sample
Ans: Population is everyone, sample is just a portion of the
population.
Why do we take samples?
Ans: Obtaining a group of people from a population in such a
way as to be representative of that population
What is the key difference between probability sampling and non-
probability sampling?
Ans: -Random or Probability Sampling: Everyone in the
population has an equal chance of being included
Follows mathematical guidelines and theory that allow us to
calculate with 95% confidence that the sample results can be
generalized
-Not everyone in the population has an equal chance of being
chosen (Sampling for a specific purpose. Only those who fit
certain criteria)
What is a sampling frame?
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Ans: All messages or people to be surveyed within our
population (List of registered voters in Orange County)
Universe
Ans: -Specify boundaries of what's being explored
-Operational definitions: Topic area, time period, sources
What are the types of non-probability samples?
Ans: -Available/Convenience ("man on the street"): Mall
intercept
-Purposive: Focus group participants (Selected for specific
purpose, not to be representative)
-Quota: Selected to represent quotas of participants t hat exist
in your population (Previous research said population is 40%
male, so you survey 40/100 males)
-Snowball: Identify small sample of population and then use a
"pass-along" method
What are the types of probability samples?
Ans: -Simple Random Selection
-Random Sampling
-Single or multi stage
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-Systematic Random Selection
-Stratified Random Selection
What is Simple Random Selection?
Ans: -Ex. List of all home addresses in prime TV viewership
market
-Start at an arbitrary point
-Follow our list of all household addresses in the TV market
-Use a random number generator until we meet our sample size
-Uses a randomly selected start number
Each unit has an equal chance of being selected
With or Without Replacement
Random Sampling
Ans: Everyone in the sample has an equal chance of being
chosen and responding (Regardless of researcher biases)
Allows researcher to infer beyond the sample to the population
by knowledge of Population parameters (characteristics)
Estimating accuracy
Estimating error of measurement
Single or Multi stage
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Ans: Cross-sectional (single time)
Longitudinal
-Trend: Randomly selected different people from a --population
over time
-Panel: The same randomly selected people from a population
over time
Systematic Random Selection
Ans: -Uses a sampling interval to select every nth unit; Widely
used
-Subject to periodicity issues: Order of units in a list may
introduce bias into selection
Stratified Random Selection
Ans: Chosen units represent a % of the population drawn at
random from that population; Similar to quota sampling, but
done so with measures put into place to make it random
Standard Error
Ans: the standard deviation (or how samples deviate from the
population)
-Regular old random error
All rights reserved © 2025/ 2026 |
MMC 3420 EXAM 2 Questions and Correct
Answers/ Latest Update / Already Graded
Distinguish between a population and a sample
Ans: Population is everyone, sample is just a portion of the
population.
Why do we take samples?
Ans: Obtaining a group of people from a population in such a
way as to be representative of that population
What is the key difference between probability sampling and non-
probability sampling?
Ans: -Random or Probability Sampling: Everyone in the
population has an equal chance of being included
Follows mathematical guidelines and theory that allow us to
calculate with 95% confidence that the sample results can be
generalized
-Not everyone in the population has an equal chance of being
chosen (Sampling for a specific purpose. Only those who fit
certain criteria)
What is a sampling frame?
All rights reserved © 2025/ 2026 |
, Page |2
Ans: All messages or people to be surveyed within our
population (List of registered voters in Orange County)
Universe
Ans: -Specify boundaries of what's being explored
-Operational definitions: Topic area, time period, sources
What are the types of non-probability samples?
Ans: -Available/Convenience ("man on the street"): Mall
intercept
-Purposive: Focus group participants (Selected for specific
purpose, not to be representative)
-Quota: Selected to represent quotas of participants t hat exist
in your population (Previous research said population is 40%
male, so you survey 40/100 males)
-Snowball: Identify small sample of population and then use a
"pass-along" method
What are the types of probability samples?
Ans: -Simple Random Selection
-Random Sampling
-Single or multi stage
All rights reserved © 2025/ 2026 |
, Page |3
-Systematic Random Selection
-Stratified Random Selection
What is Simple Random Selection?
Ans: -Ex. List of all home addresses in prime TV viewership
market
-Start at an arbitrary point
-Follow our list of all household addresses in the TV market
-Use a random number generator until we meet our sample size
-Uses a randomly selected start number
Each unit has an equal chance of being selected
With or Without Replacement
Random Sampling
Ans: Everyone in the sample has an equal chance of being
chosen and responding (Regardless of researcher biases)
Allows researcher to infer beyond the sample to the population
by knowledge of Population parameters (characteristics)
Estimating accuracy
Estimating error of measurement
Single or Multi stage
All rights reserved © 2025/ 2026 |
, Page |4
Ans: Cross-sectional (single time)
Longitudinal
-Trend: Randomly selected different people from a --population
over time
-Panel: The same randomly selected people from a population
over time
Systematic Random Selection
Ans: -Uses a sampling interval to select every nth unit; Widely
used
-Subject to periodicity issues: Order of units in a list may
introduce bias into selection
Stratified Random Selection
Ans: Chosen units represent a % of the population drawn at
random from that population; Similar to quota sampling, but
done so with measures put into place to make it random
Standard Error
Ans: the standard deviation (or how samples deviate from the
population)
-Regular old random error
All rights reserved © 2025/ 2026 |
