The Relationship Between Population, Sample & Generalizability

Coming up next: Probability Sampling Methods: Definition & Types

You're on a roll. Keep up the good work!

Replay
Your next lesson will play in 10 seconds
• 0:07 Sampling
• 1:33 Population and Sampling Frame
• 2:58 Representativeness
• 5:11 Generalizability
• 6:33 Lesson Summary

Want to watch this again later?

Timeline
Autoplay
Autoplay
Speed

Recommended Lessons and Courses for You

Lesson Transcript
Instructor: Natalie Boyd

Natalie is a teacher and holds an MA in English Education and is in progress on her PhD in psychology.

Researchers try their best to gather a sample that represents their population. But why is this important? In this lesson, we'll look at the relationship between population, sample, and generalizability in research.

Sampling

Matt is a psychologist who is interested in studying how much children remember from watching a television show about science. He wants to know if this could be a good educational tool for schools to use to help support children in learning scientific concepts.

So, Matt decides to do a study: he'll show the television show to students and then give them a short science quiz to see if they remember what the show taught.

That seems pretty straightforward, but even before he begins the study, he's faced with questions: what students should he show the program to? First graders? Third graders? Children in city schools or rural schools?

Matt's questions center around his sample, or the group of subjects in a study. Since it's not practical for Matt to test every single kid in the world, he has to narrow it down a bit.

Sampling is the process whereby a researcher chooses the sample for his or her study. For example, Matt might choose to test only students at a particular school or only students of a particular age. Maybe he chooses his sample based on gender or favorite book. There are many ways he can choose his sample.

Let's look closer at the relationship between samples, populations, and generalizability of results.

Population & Sampling Frame

OK, so Matt wants to know how much children remember from the television show. If he's really interested in studying how much all children from around the world remember, that's a lot of children and, as we mentioned before, he has to narrow it down a bit.

The population of a study is the group of people that a researcher is interested in. Usually, the population is too large to actually measure. For example, Matt's population might be every child in the entire world.

Even if a population isn't as big as every child in the world, it can still be too big to study. For example, maybe Matt's not interested in every child in the world. Maybe he's just interested in every child in the school district where he works. That can still be a very large number of students!

To narrow it down, Matt has to choose who to study from a sampling frame, or group of people from which a sample is drawn. Maybe Matt chooses a specific elementary school to do his research at. His population might be the children in the entire district, and his sampling frame is all the children at the entire school.

To unlock this lesson you must be a Study.com Member.

Register to view this lesson

Are you a student or a teacher?

See for yourself why 30 million people use Study.com

Become a Study.com member and start learning now.
Back
What teachers are saying about Study.com

Earning College Credit

Did you know… We have over 200 college courses that prepare you to earn credit by exam that is accepted by over 1,500 colleges and universities. You can test out of the first two years of college and save thousands off your degree. Anyone can earn credit-by-exam regardless of age or education level.