Sampling

• What is the first step a researcher must take regarding participants in an investigation?

  The researcher needs to decide how they select participants.
• What is the definition of a population in research?

  The population is a group of people from whom the sample is drawn.
• If a sample is taken from sixth formers in London, to whom can the findings be applied?

  The findings can only be applied to that certain group of people.
• What are the various methods a researcher can use to select participants?

  • Opportunity sampling
  • Random sampling
  • Systematic sampling
  • Stratified sampling
  • Volunteer sampling
• What is opportunity sampling?

  Participants are recruited conveniently as they are available at the time of the study.
• How does random sampling ensure fairness in participant selection?

  All members of the population have the same equal chances of being selected.
• What method is used in random sampling to select participants?

  A random number table, generator, or lottery method is used.
• What is systematic sampling?

  A predetermined system is used to select every nth member from the sampling frame.
• What is a strength of opportunity sampling?

  It is an easy method of recruitment that is time-saving and less costly.
• What is a limitation of opportunity sampling?

  It is not representative of the whole population, hence lacks generalizability.
• What is a key limitation of random sampling?

  Researcher bias can be present if the selection is not truly random.
• What is volunteer sampling?

  Participants self-select to take part in the study, often in response to an advertisement.
• What is a strength of volunteer sampling?

  It provides quick access to willing participants, making it easy and not time-consuming.
• What is a limitation of volunteer sampling?

  It may attract a particular profile of a person, affecting generalizability.
• What could influence participants' seriousness in a volunteer study?

  Motivations like money could drive participation, influencing the results.
• What is stratified sampling and its process?

  • Composition of the sample reflects varying proportions of subgroups (strata).
  • Identify strata.
  • Calculate required proportion for each stratum.
  • Select sample at random from each stratum using a random selection method.
• What is a limitation of stratified sampling?

  A complete representative representation of the target population is not possible.
• What is a strength of stratified sampling?

  It produces representative data due to the proportional strata, hence generalization is possible.
• What is a limitation of volunteer sampling regarding participant selection?

  Participants can refuse to take part, leading to an unrepresentative sample.
• What is a strength of volunteer sampling regarding participant cooperation?

  As participants are willing to take part, they are more likely to cooperate in the study.
• What is a limitation of systematic sampling regarding bias?

  It is not truly unbiased unless a random number generator is used.