sampling technique

• Outline the volunteer sampling technique


  consists of people who volunteered to be in the study
• What are the strengths of the volunteer sampling technique?


  • ease of formation
  • less chance of 'screw you' demand characteristic as participants are eager to take part so will not want to sabotage the study
• What are the weaknesses of the volunteer sampling technique


  • unrepresentative - those who volunteer may have similar characteristics
  • demand characteristics - participants often eager to please
• Outline the opportunity sample technique


  participants who are both accessible and willing to take part are targeted
• What are the strengths of the opportunity sampling technique?


  • easy and inexpensive
  • applicable in natural experiments
• What are the weaknesses of the opportunity sampling technique?


  • unrepresentative - subject to bias as participants normally collected in same community = not generalisable to society
• Outline the systematic sampling technique


  selecting from a target group (e.g, every fourth person on the list) that is not an equal chance
• What are the strengths of the systematic sampling technique?


  • randomisation = unbias + representative sample = generalisable
• What are the weaknesses of the systematic sampling technique?


  • not randomised = bias (e.g, androcentric) - less generalisable
• Outline the random sampling technique


  each member has an equal chance of being selected for a sample
• What are the strengths of the random sampling technique?


  • high chance of a representative sample as an unbiased selection = generalisable
• What are the weaknesses of the random sampling technique?

  • minority groups may distort the results
  • impractical - difficult to get full details + consent of target population
• Outline the stratified sampling technique


  divides the target group into sections with key characteristics then each section is sampled individually
• What are the strengths of the stratified sampling technique?


  • avoids bias
  • representative
• What are the weaknesses of the stratified sampling technique?


  • time + resource demanding
  • difficult to ensure each characteristic present is selected + knowledge of all characteristics may be unethical/personal