Introduction
Non-probability sampling does not give every member an equal chance of selection.
These methods are easier and faster but may introduce bias.
Types of Non-Probability Sampling
1. Convenience Sampling
Participants are selected because they are easy to reach.
Example:
Surveying nearby classmates.
2. Purposive Sampling
Researchers select participants with specific characteristics.
Example:
Interviewing experienced nurses only.
3. Snowball Sampling
Participants help recruit other participants.
Example:
Research involving hard-to-find communities.
4. Quota Sampling
Researchers collect data until a required number is reached.
Example:
Collecting responses from 50 men and 50 women.
Advantages
- Fast
- Affordable
- Useful for exploratory research
Disadvantages
- Higher risk of bias
- Results may not represent the population
Reflection Question
Which non-probability method would work best for interviewing experts?