Systematic sampling involves what method of selection?

Systematic sampling is a method used in research to select participants from a larger population in a structured manner. The technique involves selecting every Nth person from a list or sequence of individuals in the sample frame. This method ensures that the selection process is orderly and can help in achieving a representative sample if the initial sampling frame is randomly ordered.

The rationale behind selecting every Nth person is that this approach provides a systematic way to sample while reducing the potential for bias that may come from more arbitrary methods, such as preference-based selections. For instance, if a researcher has a list of participants ordered in some way and decides to select every 10th individual, this method can help in maintaining a degree of randomness while also ensuring a spread of individuals throughout the population.

In contrast to systematic sampling, the other methods mentioned in the options typically introduce a level of bias or lack of randomness. Choosing based on researcher preference can skew results, random selection from a defined pool provides flexibility but lacks the systematic approach, and selecting only the first few volunteers might not capture the diversity of the broader population adequately. So, systematically selecting every Nth person provides a balanced method that can lead to more reliable and valid research findings.