5. Sampling and sampling methods Flashcards
What are the two types of sampling methods
Representative samples
Non-representative samples
What are the types of representative samples
- Random sample
- Stratified sample
- Quota sample
- Systematic sample
What are the types of non-representative samples
- Snowball sample
- Volunteer/self-selecting sample
- purposive and opportunity sample
What is a sample frame
This is a list of all the members of the target population EG: Register in school
What is a random sample
Everyone has the same chances of being picked.
this has a possibility that the sample might not be representative as it could be disproportionate
What is a Stratified sample
The population is divided up into groups EG: Age then each section is sampled allowing there to be a correct proportion but it still requires a sample frame but it has to have relevant information about populations characteristics
What is a quota sample
The researcher calculates how many people from each group is required, the researcher then approaches people who match characteristics until the quota is filled this is used by market researchers in public places
What is a systematic sample
It involves having a systematic approach EG: taking every 10th name on a list, not everyone has an equal chance of being picked but its seen as fair
What is snowball sampling
Researchers rely on a gatekeeper to gain access to a group, the gatekeeper then introduces researcher to another person from there then this is repeated.
This is used for hard to reach groups but it unlikely to representative
what is a volunteer sample
People are invited to volunteer for research its unlikely to be representative
what is purposive sampling
When a researcher has restricted time and money or theres no sample frame, they set out to find people with characteristics that are relevant to the purpose of the study
What is opportunity sampling
This sample is made up of people who are readily available, willing and suitable to do the study.
