Probability Sampling Methods: Definition & Types

An error occurred trying to load this video.

Try refreshing the page, or contact customer support.

Coming up next: Probability Sampling Methods: Multistage, Multiphase, and Cluster Samples

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

Take Quiz Watch Next Lesson
Your next lesson will play in 10 seconds
  • 0:05 Probability Sampling
  • 1:37 Simple Random
  • 2:46 Systematic
  • 4:00 Stratified
  • 5:05 Lesson Summary
Add to Add to Add to

Want to watch this again later?

Log in or sign up to add this lesson to a Custom Course.

Login or Sign up


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.

Choosing a sample is one of the most important steps in research. But how should you choose? In this lesson, we'll look at three types of probability sampling: simple random, systematic, and stratified sampling.

Probability Sampling

Laura is a psychologist who is interested in studying whether there is bias against women in the workforce. So, she decides to survey workers to see if they believe that sexism plays a part at their company.

Who should Laura give the survey to? The sample of a study is the group of subjects that are involved in the study. The sample is an important part of the study and can influence the outcome. For example, if Laura only gives the survey to men, her results might underestimate whether workers believe there is a bias against women because men are less likely to notice or admit that sexism is a part of the workplace culture.

Not only that, but if Laura gives the survey only to women who work in fields that are female-dominated, like teachers or nurses, they might report less bias than if she gives the survey to women who run companies or work in sales or science.

From these examples, you can probably guess that sampling, or the process whereby a researcher chooses a sample, is an important part of planning a study.

One type of sampling is probability sampling, which is when the researcher chooses subjects randomly to be part of a sample. Randomly choosing subjects can increase the chance that a sample will reflect the population at large; Laura, for example, is less likely to end up with all men if she randomly chooses subjects.

Let's look closer at three types of probability sampling: simple random, systematic, and stratified sampling.

Simple Random

Imagine that Laura decides that she just wants to know if there is bias against women who work in sales at large companies. The population that she wants to generalize to is just women who work in sales at large companies, which is a much smaller and simpler population than women who work in any career in any company.

To unlock this lesson you must be a Member.
Create your account

Register to view this lesson

Are you a student or a teacher?

Unlock Your Education

See for yourself why 30 million people use

Become a member and start learning now.
Become a Member  Back
What teachers are saying about
Try it risk-free for 30 days

Earning College Credit

Did you know… We have over 160 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.

To learn more, visit our Earning Credit Page

Transferring credit to the school of your choice

Not sure what college you want to attend yet? has thousands of articles about every imaginable degree, area of study and career path that can help you find the school that's right for you.

Create an account to start this course today
Try it risk-free for 30 days!
Create An Account