Sampling Methods

Cards (12)

  • Random sampling
    Gives each member of the population an equal chance of being selected
  • Stratified sampling
    Creating a sample that's similar to your target population by using percentages -> percentage in the sample is the same as the entire population
  • Opportunity sampling
    Sampling whoever is around at the time -> nearest and most convenient people that are willing to take part
  • Volunteer sampling
    Having people volunteer to take part in the experiment
    -> putting up a poster/advert asking for ppts to self-select themselves and take part in your research
  • Strengths of random sampling
    • All members have an equal chance of being selected
    • quick
  • Weaknesses of random sampling
    may have more of a minority group and thus not be representative of the wider population
    had to recreate
  • Strengths of stratified sampling
    Sample is spread evenly throughout groups in the population -> accurate representation
  • Weaknesses of stratified sampling
    • Can be very time consuming
    • categories have to be identified and calculated -> not easy to categorise people, may ignore important strata
    • requires details from the population
  • Strengths of opportunity sampling
    Easiest and most convenient method
  • Weaknesses of opportunity sampling
    Unrepresentative, sample is drawn from a small population
  • Strengths of volunteer sampling
    • ppts less likely to drop out (committed)
    • ppts are willing to partake
  • Weaknesses of volunteer sampling
    • Only tend to attract outgoing people with an interest in research -> only get results from those who volunteer, which may not be representative of the larger population
    • factors may affect who takes part
    • may not get high enough numbers