Share on Show What is Probability Sampling?Sampling takes on two forms in statistics: probability sampling and non-probability sampling:
Probability sampling is based on the fact that every member of a population has a known and equal chance of being selected. For example, if you had a population of 100 people, each person would have odds of 1 out of 100 of being chosen. With non-probability sampling, those odds are not equal. For example, a person might have a better chance of being chosen if they live close to the researcher or have access to a computer. Probability sampling gives you the best chance to create a sample that is truly representative of the population. As a rule of thumb, your sample size should be over about 30. If you have a small sample, you may need to try one of the non-probability sampling techniques instead. Watch the video for an overview of probability sampling: Probability Sampling Methods Watch this video on YouTube. Cant see the video? Click here. Types of Probability Sampling
Advantages and DisadvantagesEach probability sampling method has its own unique advantages and disadvantages. In general, probability sampling minimized the risk of systematic bias. This means that you are reducing the risk of over- or under-representation--ensuring your results are representative of the population. Using probability sampling also means that you can use statistical techniques like confidence intervals and margins of error to validate your results. Advantages
Disadvantages
ReferencesCook, T. (2005). Introduction to Statistical Methods for Clinical Trials (Chapman & Hall/CRC Texts in Statistical Science) 1st Edition. Chapman and Hall/CRC CITE THIS AS: Need help with a homework or test question? With Chegg Study, you can get step-by-step solutions to your questions from an expert in the field. Your first 30 minutes with a Chegg tutor is free! Comments? Need to post a correction? Please post a comment on our Facebook page. StatisticsHowTo Facebook Page |