Sampling, Random

Defining a Random Sample

The sampling method refers to the way researchers select a group of subjects for analysis from a larger population for which a generalization is sought. Usually, in communication research the desire becomes to generate data from a sample comprised of human participants. However, within communication research the population of interest could represent some class of messages (like fear appeals) and the researcher seeks to generalize from a random sample to all such examples of that class of messages. The most commonly referenced method of random sampling is known as simple random sampling, but random sampling could involve specific methods of systematic or stratified sampling.

Random sampling provides a method to enable a researcher to obtain data from a representative sample of participants that most resembles, and contains elements of, the population of interest. Additionally, obtaining a random sample allows communication researchers to make inferences from the findings about the population of interest. In the case of a completely enumerated and available sample, basically, when the characteristics of the population are known and well defined, each participant is chosen completely at random and the chance of selection is the same for all individuals. In other words, a random sample is meant to be an unbiased subset of the population. When the selection process permits each member of a population equal chance of selection, a random sampling method takes place.

Use of a random sampling methods provides the highest probability for obtaining a sample that is unbiased and representative of the population [Page 1542]of interest, and therefore increases the accuracy with which findings can be generalized to that population.

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