Sampling

• What is random sampling?

  all members of the target population have an equal chance of being selected
• what is systematic sampling?

  every nth member of target population is chosen
• what is stratified sampling?

  choosing sample in the same proportions as they are in the target population (60% men 40% women)
• what is opportunity sampling?

  selecting anyone who is willing and available
• what is volunteer sampling?

  participants selecting themselves
• evaluate random sampling?

  • strength- free from researcher bias
  • limitation- difficult and time consuming, may be unrepresentative
• evaluate systematic sampling?

  • Strength- avoids researcher bias, fairly representative
  • Limitation- complete representation is not possible
• evaluate stratified sampling?

  • strength- avoids researcher bias, representative
  • limitation- complete representation not possible
• evaluate opportunity sampling?

  • strength- saves time, effort and money
  • limitation- researcher bias, unrepresentative of target population
• evaluate volunteer sampling?

  • strength- easy as participants come to you
  • limitation- volunteer bias (can attract a certain profile of a person who is helpful,keen and curious)