Stratified Random Sampling

Stratified Random Sampling

1. Population is divided into separate groups, called Strata

2. Superior to simple random sampling

3. Strata must be non overlapping

4. Used when population is heterogeneous

5. Criterions used for stratification

   • Age
   • Gender
   • Ethinicity
   • Location
   • Socioeconomic Status
   • Educational Level
   • Criterion vary greatly study to study

6. Sample is selected from each stratum randomly