Sampling Techniques Flashcards
(18 cards)
define sampling
- how ppts are selected to take part in research
- who we select impacts our research
what is a target population?
the population of people your research is aimed at
what is a sampling frame?
a list of potential ppts from your target pop e.g. census, from this a list of ppts can be drawn
what is opportunity sampling?
taking a sample from people you have an opportunity of studying, readily available and most convenient
what is volunteer sampling?
- ppts choose themselves by responding to an advert to take part in research
- can appear in newspapers, notice boards etc
what is random sampling?
everyone in the target pop has an equal chance of being selected e.g lottery system, name generator etc
what is systematic sampling?
ppts are selected using a pre-determined system, every nth person
what is stratified sampling?
ppts selected according to their frequency in the target pop, every sub group should be represented in the study
what are the advantages of opportunity sampling?
easiest, most convenient, least time consuming
what are the limitations of opportunity sampling?
- researcher bias
- unrepresentative because it’s the only group that happens to be there
what are the advantages of volunteer sampling?
- requires little work from the researcher
- ad can be posted online so reaches a wider audience
- can target a pop based on where you advertise
what are the limitations of volunteer sampling?
- likely to have volunteer bias
- no researcher control
- unlikely to be fully representative
- ppts may only be doing it for money and not take it seriously
what are the advantages of random sampling?
no researcher bias
what are the limitations of random sampling?
- could be unrepresentative by chance,
- requires sampling frame
- ppts could turn down once picked
what are the advantages of systematic sampling?
unbiased as it uses an objective system
what are the limitations of systematic sampling?
- could be unrepresentative by chance
- requires sampling frame
- ppts could turn down once picked
what are the advantages of stratified sampling?
- most representative
- unbiased as it has ppts from each sub-group
what are the limitations of stratified sampling?
- difficult to achieve
- accurate sampling frame and correct calculations needed
- ppts in random selection may not agree
