Sampling Procedures

• Sampling Procedure:

  1. Probability Sampling - a sampling procedure where every element of a population is given an equal chance of being selected
  2. Non - Probability Sampling - a sampling procedure where not every element of the population is given equal chance of being selected - good choice because convenient
• Probability Sampling Methods

  • Simple Random Sampling
  • Stratified Random Sampling
  • Cluster Sampling
  • Systematic Random Sampling
  • Multi-Stage Random Sampling
• Simple Random Sampling


  Simplest way of getting random sample - each member has an equal chance
• Stratified Random Sampling


  Selecting a simple random sample from each subpopulation (stratum, strata)
• Cluster Sampling


  First divided into separate groups (clusters) then a simple random sample of clusters from the available clusters in the population
• Systematic Random Sampling


  Random selection of one of the first k element in ordered population, then selection every kth element thereafter
• Multi-Stage Random Sampling


  Two or more probability techniques are combined - sampling within the sample
• Non - Probability Sampling

  • Convenience Sampling - participants who are accessible and convenient to the researchers, comfortable, distance
  • Judgement Sampling (Purposive Sampling) - researchers rely on their own judgement
  • Quota Sampling - choose respondents from group until the quota is filled
  • Snowball Sampling - currently participant of your study help recruit future respondents - referral/recruitment sampling for phenomenology study - HIV sensitive case