Distinguish between random sampling and quota sampling.

Mark scheme

Marking points from the official mark scheme (May/June 2016). The mark or mark type is shown in brackets.

1. (a) Random sampling is where every member of the target population has an equal chance of being selected in a market research survey.
2. Quota sampling is where the target population has been stratified and the interviewer selects an appropriate number of respondents from each stratum.
3. Note: Do not award marks for candidates who simply repeat the words random and quota without any explanation of these terms.
4. One mark for each accurate definition given.
5. (b) Limitations could include the following:
6. Imperfect sample design
7. Inadequate budget to determine the sample, as it could be very/too expensive
8. Sample size may be too small
9. Difficulty in getting representation in the sample
10. Some sampling may be tedious and time-consuming
11. Untrained/inadequate interviewers
12. Biased, ambiguous questions
13. Could be very/too expensive.
14. Note: some candidates may interpret market research sampling as product sampling/test marketing. Please accept this interpretation and award marks according to the quality of the limitations given. Full marks can be achieved for this approach.
15. [3] Two limitations soundly explained
16. [2] One limitation soundly explained or two partially explained
17. [1] One limitation partially explained or a list of two
18. Please accept and reward other relevant points.