If your sampling frame is meaningful, convenient sampling via social networks could constitute purposive sampling (legitimate).

Hope this helps,

Matt

I know of several learners who did. Make sure it is written up in your proposal as your choice of data collection. Do not go into the group and start recruiting. You have to ask the admin first. Their reply will be your proof of permission to conduct research. Let the admin post it for you with all of the information, and allow participants to follow through. This is easier if you are conducting a quantitative study. Best wishes to you.

What is the data about? What is your research question? Are you interested in the social network connections as a source of data? Or are you simply using social network platforms as a convenience sample?

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