Sampling Techniques

• What is the population?

  Refers to the large group of individuals that the researcher is interested in studying
• What is a target population?

  A subset of the general population, more specific
• What is a sample?

  A smaller group selected from the target population
• What is a random sample?

  Where all members of the target population have an equal chance at being selected
• What is a systematic sample?

  Where every nth number of the target population is selected
• What is a sampling frame?

  A list of the target population, organised by alphabetical order ect
• What is a stratified sample?

  Where the sample reflects the proportions of the target population
• What is an opportunity sample?

  A sample of chance, asking whoever is around at the time of research
• What is a volunteer sample?

  Participants volunteer to be part of the research
• Evaluation of Random Sampling:

  • Potentially unbiased - Strength
  • Control CV's/EV's - strength
  • Time consuming - Limitation
  • May not always work - Limitation
• Evaluation of Stratified Sample:

  • Representative - Strength
  • Can't account for all subgroups - Limitation
• Evaluation of Systematic Sampling:

  • Objective method - Strength
  • Time consuming - Limitation
  • Those selected may refuse - Limitation
• Evaluation of Opportunity Sampling:

  • Convenient - Strength
  • Unrepresentative - Limitation
• Evaluation of Volunteer Sampling:

  • Easy - Strength
  • Ps are engaged - Strength
  • Volunteer bias - Limitation