A very important topic in research is representativeness. Perhaps it is even the most important topic. In case of a non-representative response, all conclusions that are drawn may be doubted.
Different views on representativeness can be distinguished. One of these is taking a random sample. However, it can be demonstrated that with random sampling at least five percent of the samples will be non-representative.
Very often, researchers claim to have drawn a representative sample. However, a representative sample is not the problem. A representative response is required. A non-representative sample can even be used as a strategy to get a representative response. All this is explained in this paper.
If you want to improve the quality of your research, make sure you have a representative response. You can learn how to achieve this in this paper.