Unit 3 Flashcards
A _____ is a collection of objects about which we want information.
Population
A ______ is a part of the population consisting of units we actually examine to gather information.
Sample
Voluntary response sampling:
People make the choice of whether or not they want to participate.
Connivence sampling:
Only sampling people that are easily available; ie. only sampling people that are in line for coffee with you.
Voluntary response samples and convince samples are _____.
Biased - The study systematically favours certain outcomes.
Simple random sampling (SRS):
An SRS of size n consists of n individuals chosen in such a way that every group of n individuals has an equal chance to be the sample selected.
Simple random sampling without replacement:
An individual cannot be chosen twice.
Probability sample:
Populations are naturally divided into groups; this gives each possible a known chance of being selected.
Stratified random sample:
Population divided into strata (a group similar in some way) then an SRS is chosen from each stratum to form the sample.
Multistage sampling:
Selecting smaller and smaller groups from a population by progressively narrowing down our sample.
The list from where the sample is drawn is incomplete = _______.
Undercoverage. (ie. unlisted phone numbers).
People may refuse to answer questions to a mail in survey = ________.
Non response.
People may lie, not remember, or be unsure of how to answer due to a poorly worded/leading question = ___________.
Response bias.
