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This guide aims to focus on core problems and difficulties which you should engage with in order to come to good sampling decisions for qualitative data.

What is sampling?

Procedure to choose, identify and gain access to the unit of your research.
(Masson 1996)

How to select sample unit?

In general, people are sample units. For analytical purposes, researchers tend to classify their sample units using different classifications. This can include:

  • Gender
  • Age
  • Ethnicity
  • Occupation
  • Place of living
  • Education, etc.

This list is not explicit, so you need to work out what are the most appropriate units of classification for sample unit in your research project?

Please view Selecting sampling unit - Guiding questions (docx) / Selecting sampling unit - Guiding questions (pdf) which may help you in selecting appropriate sample unit and justify your decision. Using 150 words try to answer each question.

Finally - How large my sample should be? When do I have enough participants?

This is not a straightforward answer. Qualitative samples are usually small. This is mainly to do with limited resources and time to generate and analyse qualitative data.

The unit that you will select will need to allow to generate data to explore process, contrast and compare similarities and differences to tst and develop theory and explanation rather than make a statistical comparison. Thus, the answer to the question will be: sample should be large enough to allow you to make comparison, explore and generate explanation.

If you can make comparison/explore and generate explanation to your research questions - your sample is large enough.

Download this guide as pdf version: Sampling unit - A guide (pdf)

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