Sampling technqieus Flashcards
What is random sampling?
Every member of the target population has an equal chance of being selected.
E.g. picking names from a hat
What are the advantages of random sampling?
It produces an unbiased representative sample of a target population
What are the disadvantages of random sampling?
It can be time consuming, especially with a large target population
What is stratified sampling?
Dividing the target population into subcategories and then selecting members of these subcategories in the proportion that they occur in the target population
What are the advantages of stratified sampling?
Might be more representative, as it identifies the important characteristics of the target population
Conclusions about differences between groups can be draws (as every group is identified and represented in the sample)
What are the disadvantages of stratified sampling?
Can be time consuming because categories must be identified and calculated
What is opportunity sampling?
Selecting subjects who are available at the time
What are the advantages of opportunity sampling?
It is quick
It is cheap
What are the disadvantages of opportunity sampling?
Can produce a biased sample because it’s easy for the researcher to select people from their own social/cultural group - this wouldn’t be representative of the target pop.
Ps may decline, which may create a self-selected sample
Researcher may choose Ps most likely to be helpful - biased sample
What is volunteer or self-selecting sample?
Individuals who have consciously or unconsciously determined their own involvement
What are the advantages of volunteer sampling?
It’s quick
Relatively easy to do
Can reach a wide variety of Ps
Convenient and ethical because people choose to take part and it is not forced upon them
Choice is not biased on the part of the researcher
What are the disadvantages of volunteer sampling?
Ps who volunteer might not represent the whole target pop. - more obedient, more motivated - bias
