Sampling Flashcards
(31 cards)
what is sampling
the researcher selecting a smaller group of people from the wider target population
target population
a population that includes all the people with the characteristics a researcher wants to investigate
sample
the group selected from the wider population to take part in research
census research
where every member of the target population is studied
representitiveness
if the sample is typical of the target population
generalisation
if the findings can be applied to the entire target population
sampling bias
any differences between the sample and the larger population
sampling frame
a list of members of the population to be studied
examples of sampling frames
electoral register
register of births
does a sampling frame make it easier to select a representative sample from the target population
yes
practical issues with sampling frames
people may be missing from the list
access to the list
sampling frames are not always suitable to the purpose of the research
‘gaining access’
finding participants and getting them to take part in the research
examples of groups which may be difficult to access
children - due to safeguarding
hospital patients
gatekeepers
people who control whether researchers can have access to participants
sampling technique
method used by the researcher to select their sample
random sampling
gives every member of the population the same chance of being chosen
non-random
not everyone in a population will stand a equal chance of being chosen
representative sampling techniques
probability
systematic
cluster
stratified
quota
non- representative sampling techniques
snowball
volunteer
opportunity
purposive
probability sampling + evaluation
ppts selected randomly from sampling frame
- ppts may geographically be spread out
- unequal selection possible
+ no bias
systematic sampling
researcher selects every nth person from the sampling frame
+ no bias
-unequal selection possible
cluster sampling
target population split into groups and then some of the clusters are sampled
+some control over sample
- researcher bias
stratified sampling & evaluation
divides the research population into strata using significant variables, then samples are drawn randomly from these groups
+increased representitiveness
- difficulty selection appropriate strata, cannot account for all variables
quota sampling
researchers have a list of the proportions and various characteristics of the target population
they then go out and try and find people to meet their quota
- subjective, may introduce bias
- easy to miss out influential characteristics