Sampling

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2. Sampling • Researchers aim to get a sample that is representative of the target population • Every type of person in the TP should be proportionally represented in the sample • NB: it is not necessary for the sample to be representative of the GP unless the researcher intends to generalise

3. Sampling • Opportunity sampling • Use whoever is immediately available e.g. go out and accost passers-by • Volunteer sampling • Use whoever puts themselves forward e.g. advertise in the paper

4. Sampling • Quota sampling • Design a sample to reflect the TP and then recruit to order • Random sampling • Every member of the target population has an equal chance of being selected • E.g. selected by computer from the electoral roll

5. Sampling • random • random • quota • quota How difficult to obtain • opportunity • opportunity • volunteer • volunteer How likely to be representative