Non-random Sampling
Types of Non-random sampling
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Quota Sampling
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Opportunity Sampling
Quota Sampling
- Population divided into groups based on people's characteristics.
- A quota of people in each group is set to be asked.
- E.G. If we wanted to investigate if being left-handed affects intelligence, then we would ask a set amount of left handed people and the same amount of right handed people. If we didnt do this then our results would be inaccurate because the number of right-handed people is much bigger than the amount of left-handed people.
- Since this is non-random sampling it can introduce bias.
Opportunity Sampling
- This is purely based on people who are around at the time you are interviewing. However this could cause bias. E.G. You are asking people outside the door of a boys football match. This means that there would be more boys asked than girls which causes bias.