SAMPLING METHODS

SAMPLING METHODS

1. RANDOM SAMPLING

   • PROCEDURE
     • Every member of the target population has an equal chance of being selected e.g by numbering and listing all and using a random number generator
   • STRENGTH
     • Likely to be unbiased as the researcher does not control who paricipates
   • WEAKNESS
     • Very hard to do unless you have a very small population

2. STRATIFIED SAMPLING

   • PROCEDURE
     • The sample is a proportional representation of the target population. You break the population down into groupsand recreate a smaller version e.g males and females, or by age group
   • STRENGTH
     • Very represenatative of the population if done correctly
   • WEAKNESS
     • Time consuming and difficult

3. OPPORTUNITY SAMPLING

   • PROCEDURE
     • P's are selected from whoever is available at the time e.g. whoevers in class on the day you hold your study
   • STRENGTH
     • Easy, quick and most likely ethical
   • WEAKNESS
     • Probably not very representative, as drawn from a small selection of the communiy

4. VOLUNTEER SAMPLING

   • PROCEDURE
     • P's select themselves e.g. people respond to advertisement
   • STRENGTH
     • Probably access a variety of people you would not normally have access to - likely to be motivated
   • WEAKNESS
     • Motivation may make them behave differently. Volunteers may have special qualities