Sampling Techniques

Sampling Techniques

1. Random sampling- where every member of the target population has an equal chance of being selected

   • Best technique for providing an unbiased representative sample of the target population
   • Very time consuming and often impossible with a large target population
   • eg pulling names out of a hat

2. Opportunity sample- using anyone is the target population who is available

   • Quick and cheap
   • As it only uses people who are available at this time, the sample may not be representative
   • eg everyone in café 6

3. Systematic sample- selects pps at fixed intervals

   • eg every 10th person in the list of the target population
   • fairly cheap and fast
   • eliminates possibility of bias
   • researchers need to ensure that there are no hidden bias

4. Stratified sample- a proportional sampel

   • eg if 70% of the target population were male and 30% were female, your sample needs to be 70% male and 30% female
   • provides a very representative sample
   • Time consuming and expensive