What is the purpose of snowball sampling?

Snowball sampling can be used in a number of circumstances.

Sometimes the researcher may be able to identify only a small number of individuals in the target group but these people are likely to known others in the target group, and people that they know will also know more such people-and so on. By including those few initial people in her sample, and asking them to recruit others, the researcher may be able to achieve a useable sample size.

Then, sometimes, a researcher is actually more interested in the connections between people, or in other Words, social networks. In this case, snowball sampling can be used to identify those connections.

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