Sampling Methods Flashcards
Define Target Population
The group of people that you are testing
Define Sample
What is selected to be representative of the population
What is a smapling method?
How we acquire our sample
What is an opputunity sample?
Usually use anyone who happens to be available
What is disadvatnage of oppurtunity sample?
Invariably biased
Strengths of Oppurtunity sample?
Easiest
What self-selecting sampling?
This is where participants volunteer themselves to take part in an experiment
Disadvantages of a self-selecting sample?
The results are usually biased as the type of people who usually volunteer are usually more highly motivated then randomly selected participants (volunteer bias)
Advantages of a self-selecting sample?
If you advertise in a newspaper it means you have access to a wide variety of participants
What is a random sample?
This is where participants have an equal chance of being selected
Disadvantages of Random sample?
This is an unbiased sample- though the population from which the names are drawn is based (e.g. Chenderit high School)
What is snowball sampling?
A snowball sample is one in which the researcher collects data on the few members of the target population he or she can locate
Then asks those individuals to provide information needed to locate other members of that population whom they know
Advantages of snowball sampling?
Good for difficult to locate samples
Disadvantages of the snowball sample?
Likely to be unrepresentative
What is the stratified sample?
This is when participants are selected from a sampling frame that has been stratified or layered
This means participants are put into groups and the researcher make sure these groups are represented in the final sample
A certain number is selected (usually randomly) so they are represented proportionally in the final sample
