Purposive Sample

Purposive sampling is a non-probability sampling technique in which the researcher deliberately selects participants because they have specific characteristics, knowledge, or experience relevant to the study.

Transcript

1. M.Ed | RESEARCH METHODOLOGY Purposive Sampling A simple guide to choosing participants with a purpose Sobin Sony Alex M.Ed First Year
2. What is Purposive Sampling? Also known as Judgmental sampling The researcher deliberately chooses people who have the knowledge or experience the study needs. Selective sampling The focus is on information-rich participants, not on random selection. A non-probability sampling method
3. Key Characteristics Non-random Participants are not picked by chance Judgment-based Chosen with a purpose, not by chance The researcher decides who fits the study Purpose-focused Every choice links to the research aim Mostly qualitative Common in interviews and case studies Small sample Fewer participants, deeper information
4. Concept Map Meaning Types Deliberate choice of participants Six main kinds Uses Qualitative and case studies Characteristics Non-random, judgment-based Purposive Sampling Advantages Rich, focused information Steps Five simple stages Limitations Bias, hard to generalise
5. Types of Purposive Sampling 1 Maximum variation Choose people with very different views or backgrounds. 4 Extreme case Choose unusual or exceptional cases (also called deviant). 2 Homogeneous Choose people who share similar traits or experiences. 5 Critical case Choose cases that strongly show or test an idea. 3 Typical case Choose average, everyday cases that represent the norm. 6 Expert sampling Choose people with special knowledge of the topic.
6. Steps in Purposive Sampling 1 2 3 4 5 Define the purpose Set the criteria Identify participants Select and contact Collect data What do you want to find out? Who can give useful information? Find people who match the criteria. Invite them to take part. Interview, observe or survey. Tip: keep checking that every participant fits your purpose.
7. Advantages and Limitations + Advantages – Limitations • Saves time and effort • Researcher bias can affect choices • Gives rich, relevant information • • Works well for small or hard-to-reach groups Results cannot be generalised to everyone • Depends heavily on the researcher’s judgment
8. Example from Education Research topic Classroom management strategies Teachers in one school Population All teachers in a school Purposive choice Only experienced teachers, because they can share the richest insights Selected: experienced teachers Not selected
9. Conclusion 1 Purposive sampling selects participants on purpose, using the researcher’s judgment. 2 It suits qualitative research that needs rich, detailed information. Thank You Any questions? 3 Clear selection criteria reduce bias and keep the study focused.