ENG518 Research Methodology in ELT Assignment 1 for Fall 2026, from the BS Applied Linguistics program, carries 20 marks and asks a single question on choosing a sampling technique. A researcher wants to explore the challenges faced by secondary-school English teachers who have at least five years of experience teaching writing skills. Check VULMS for the due date. The solution file linked below argues for purposive criterion sampling and justifies the choice in full.
What Does the Solution File Cover?
Which Sampling Technique Is Most Suitable?
Purposive sampling, specifically criterion sampling. Purposive sampling is a non-probability technique in which the researcher deliberately selects participants with characteristics that are directly relevant to the research question. In criterion sampling, clear criteria are set in advance and only participants who meet them are included. Here the criteria come straight from the study: the participant must be a secondary-school English teacher with at least five years of experience teaching writing skills.
Why Does Criterion Sampling Fit This Study?
Only teachers who meet the criteria can describe the challenges from direct, sustained experience, so criterion sampling guarantees that every participant is information-rich for the exact question asked. The study is exploratory and qualitative, seeking depth of understanding rather than numbers that generalize to a whole population, and purposive sampling is designed for that depth. It is also practical: the researcher can recruit through schools, head teachers and professional networks, and can add snowball sampling as a supplement if eligible teachers are hard to reach. The same concise question and answer style is used in the ENG507 Assignment 1 solution published alongside this one.
Why Is Probability Sampling Unsuitable Here?
A complete and accurate list of all secondary-school English teachers with five or more years of writing teaching experience may not exist, and random selection from a general teacher population would include many teachers who do not meet the criterion. That would waste time and resources and could still miss the most experienced voices, while adding nothing to the depth of the findings. The solution file also notes the honest limitation: findings from purposive sampling cannot be statistically generalized, so the selection criteria must be stated clearly and reported transparently.
How Do You Download the Solution File?
You can download the complete solution file from Google Drive using the link below. It contains the full question, the choice of purposive criterion sampling, four reasons for the choice, the limitation, and a conclusion that ties the technique to the research question.
Frequently Asked Questions
What Is the Difference Between Purposive and Criterion Sampling?
Criterion sampling is a type of purposive sampling. In purposive sampling the researcher uses judgment to select information-rich participants. In criterion sampling that judgment is formalized: preset criteria decide who qualifies, and everyone who meets them can be included.
Can the Findings of This Study Be Generalized?
Not statistically, because participants are chosen by judgment rather than at random. Readers can still judge transferability when the researcher reports the selection criteria transparently, which is why the solution file states the criteria explicitly.
When Should Snowball Sampling Be Added?
When eligible teachers are hard to reach through schools and networks. Participants can recommend other experienced colleagues who meet the same criteria. Snowball sampling then supplements the core technique, which remains purposive criterion sampling.
Last updated: November 2026.
