were all participants have an equal chance of being selected
Systematic sample
every nth member of a target population is selected and a sampling frame is produced
systematic sample strength
Strengths: avoids researcher bias
systematic sample weakness:
Weakness: also difficult to achieve/ time consuming
Stratified sample
the researchers identifies the different types of people that make up the target population and work out the proportion needed for sample to be representative
Stratified sample Strength
Strength: avoids researcher bias and is representative of population
Stratified sample
Weakness: is not perfect
Opportunity sample
those people who are avalible at the time and willing to participate
Opportunity sample
Strength: quick and convenient
Opportunity sample
Weakness: unrepresentative of target population, researcher bias
Volunteer sample
participants put themselves forward to be a part of the sample