Identifying the research participants
Sampling refers to the process of selecting a smaller group of individuals or units from a larger population. The aim is to use their responses or behaviors to draw conclusions about the larger population.
In probability sampling, each member of the population has an equal chance of being selected. This technique is used in quantitative research to ensure that the sample is representative of the population being studied.
Some probability sampling techniques include:
- Simple random sampling: Randomly selecting participants from a sampling frame
- Systematic random sampling: Selecting every *N-*th person from a flow of people as your participants
- Stratified random sampling: Dividing the population into groups based on specific criteria and randomly selecting participants within these groups
- Cluster sampling: Creating a list of clusters based on specific criteria and randomly selecting some of these clusters, then randomly selecting participants within the selected clusters
Non-probability sampling involves selecting participants based on subjective criteria and is used in qualitative research. These techniques are used to obtain a more in-depth understanding of a particular group of people.
Some non-probability sampling techniques include:
- Convenience sampling: Selecting participants who are readily available — for example, people in a waiting room
- Self-selective sampling: Participants voluntarily choose to participate in a study without specific criteria, for example, by clicking on a link on a company website
- Snowball sampling: Starting with a few participants and asking them to recommend others who meet specific criteria
- Extreme case sampling: Selecting participants who represent extreme or unusual positions, such as early adopters of a new technology
- Emergent sampling: Following new leads during fieldwork as they unfold to flexibly take advantage of new knowledge
- Maximum-input sampling: Selecting participants with a comprehensive overview of an entire experience or system to get a maximum of input from them[1]
