what are the sampling techniques?
volunteer
opportunity
random
stratified
what is volunteer sampling?
people have chosen themselves to take part
can be through replying to advertisements
self selecting
what is a strength of volunteer sampling?
quick and easy,more ethical as ppts give consent through volunteering to take part
what is a weakness of volunteer sampling?
can create a unrepresentable as only certain ppts want to take
can be certain interests
what is opportunity sampling?
selecting people who are available at the time
what is a strength of opportunity sampling?
quick and easy way of obtaining participants
what is a weakness of opportunity?
may not present a representable sample
researcher bias
what is random sampling?
everyone in a target population has an equal chance of taking part
numbering or naming the populaion and using some type of raffle to pick
what is a strength of random?
provides the best was of reducing bias as everyone has an equal chance of being picked
what is a weakness of random?
very difficult to achieve
money time etc
need to name them all but then not use them
what is stratified sampling?
researcher identifies different groups in a target population and then works out their proportion of each
what is a strength of stratified sampling?
all different groups are included in the sample so is the most representable
easilty generalisable
what is a weakness of stratified
very time consuming
dividing categories
