Sampling Flashcards
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
snowball sampling
initial contact is made with a participant who puts the researcher in touch with others
+ useful for researching sensitive, hidden or criminal groups
- not representative
- trail of participants may dry up
volunteer sampling
an advert is placed and people volunteer to take part in the research
+ consent guaranteed
- location of advert may impact representativeness
-volunteers often systematically different to others
opportunity sampling
participants are selected based on their availability
- may not be representative
- limited control over sample characteristics
purposive sampling
researcher finds participants to suit their purposes
+ can improve representativeness by finding people to make up for bias in the original sample
+ can disprove findings of other research by finding the exception to the rule
- researcher bias
- limited generalisability as sample is not random
CSEW - sampling technique used and choice for it
probability sampling - sampling frame royal mail list of addresses
75,000 households - selected to represent the population as a whole
when an address has been selected it cannot be replaces with another address
Learning to Labour - Willis
opportunity sampling - 12 working class white boys who attended one boys only secondary school
working class boys selected as the aim was to see why working class children went into working class jobs
volunteer sample
ppts have volunteered themselves to take part in a study
