It depends on you research question. Choose wisely!! Did you know that choosing the wrong sampling method can skew your research results by up to 30%?
Probability Sampling: the Quantitative Champion
- Simple random ➡Everyone gets an equal shot at being picked.
A high school principal wants to survey 100 students about their cafeteria experience. She puts all 1000 student names in a hat and randomly draws 100.
- Systematic ➡It’s like picking every 10th person in line in a systematic way.
A grocery store wants to survey every 20th customer who checks out. They start with a random number between 1 and 20, then select every 20th person after that.
- Stratified ➡ Divide and conquer!
Split your population into sub-groups (strata) and sample from each. When you want to make sure every subgroup gets its moment in the spotlight. A university researcher wants to study student satisfaction. She divides the student body into strata (freshmen, and seniors) and randomly samples from each group.
- Cluster ➡ Think of it as sampling neighborhoods instead of individual houses.
When your population is spread out, and you can’t be everywhere at once, divide into clusters based on geography. A national health survey randomly selects 50 cities across the country, then surveys all households within those chosen cities.
Non-Probability Sampling: The Qualitative Hero.
1.Convenience ➡The “grab what you can get” approach. When you’re short on time or resources and need quick insights.
A psychology student conducts a study on stress levels by asking fellow students in his dorm to participate.
- Judgmental or Purposive ➡Hand-picking participants based on your expert judgment.
When you need specific insights from the cream of the crop. A researcher studying the effects of meditation on chronic pain specifically selects participants who have been practicing meditation for over 5 years and have chronic pain conditions.
- Snowball ➡Let your participants lead you to more participants!
When you’re trying to reach hidden or hard-to-find groups. A sociologist studying the experiences of transgender individuals in the workplace asks initial participants to refer other potential participants from their community.
- Quota (Ql & Qn) ➡Fill your sample quota with specific characteristics.
When you want a mix of structure and flexibility in your sample. A market researcher wants to test a new product. She ensures her sample includes specific quotas: 50% male and 50% female, with equal representation from different age groups and income levels.