What is the difference between a convenience and random sample?
Convenience sampling only occurs when you take your sample from a group that’s easiest to contact or study, such as asking people from a specific area close to your testing center to participate in your study, or only sampling people in a certain employee database, just because it’s more convenient. It causes undercoverage and bias because people from other areas and demographics do not have a chance to respond, and thus overall opinion is skewed. Asking everyone from a certain group to be part of a study wouldn’t be convenience sampling, it would be cluster sampling. Selecting a certain amount of people from a convenient group randomly would probably still be classified as convenience sampling, though it could easily be regarded as a combination of the two.
