Sampling Flashcards
what is sampling
the process of selecting a representative group from the population under study.
what is a sample
the group of people who take part in the investigation.
what is the target population?
the total group of individuals from which the sample might be drawn.
random sampling?
where each member of the target population has an equal chance of being selected
eval of random
S: unbiased selection
generalisation
W: can produce unbiased sample
impractical as not everyone may be accessible
opportunity sampling?
Uses people from target population available at the time and willing to take part. It is based on convenience.
eval of opp?
S: Easy formation
W: ma not provide a representative sample
volunteer sampling?
people who volunteer to participate in the research - select themselves often by replying to adverts
eval of volunteer sampling?
S: p’s will have given informed consent
w: might be biased only receive one type of people -, no volunteers
systematic sampling?
selects p’s in a logical way from the target population, like every nth participant on a list of names.
eval of systematic sampling?
S:provides a representative sample
W: Only possible if you can identify all members of the target pop.
stratified sampling?
when the researcher identifies the different types of people that make up the target pop and works out the proportions needed for the sample to be representative.
eval of stratified?
S: highly representative of the target pop - generalisation
W: Time consuming to gather and difficult to do
