Non-probabilistic samples can be adequate when there is no pretension to generalize the results, to avoid the cost of the probabilistic one, for lack of time or in “pilot” or preliminary tests. They are usually used in an exploratory way or for a qualitative methodology (Delphi technique, focus group, discussion groups, life stories, interviews). Intentionally, controlled by the researchers, the participants are chosen for their suitability.

Non-probabilistic samples can be:

Convenience samples

Strategic samples

Other types of samples