Sampling Flashcards
Define target population
The group of people the researcher is interested in studying
Define sample
The actual group of participants used in the study.
Define random sampling
Each member of the target population has an equal chance of being selected e.g all names placed into a hat and and first 20 picked will be the sample
Strengths of random sampling
Sample should be representative of the target population and eliminate sampling bias
Weaknesses of random sampling
Difficult to include all names of target sample, may end up bias depending on who chooses to actually take part
Define snowball sampling
When participants are asked to contact their friends and family to ask the, to take part in research and they then ask other people
Strengths of snowball sampling
Enables access to populations hard to find e.g drug users/sex workers. It is cheap as no advertising needed. Easy as a few people recruit more and more (saves time), sample could be diverse as allows access so increased generalisability?
Weaknesses of snowball sampling
May be bias as have similar interests/ personalities, limits generalisability . Also may not get enough people.
Define opportunity sampling
Sample produced by selecting those who are most available at a given time and place selected by the researcher
Strengths of opportunity sampling
Quick and easy way of choosing ps
Weaknesses of opportunity sampling
May be bias due to location and availability, ps may feel obligated to take part
Define self selecting sampling
When people volunteer to take part in a study .often adverts, posters or leaflets will be distributed which contain details of the research and contact details.
Strengths of self selecting
People are more likely to participate as chose to reply, ethical as they volunteered (consent)
Weaknesses of self selecting sampling
Could be bias as they May have characteristics making them more willing to take part. Time and cost to make and distribute adverts
