Wondering how to select a representative sample from a given population? Researchers use what is called a “sampling frame,” or an inventory of all potential participants (Evans & Rooney, 2011). To be included in the sampling frame, potential participants must possess certain characteristics that you, as a researcher, are interested in. You might define your sampling frame with inclusion and/or exclusion criteria. Inclusion criteria are the attributes that people must possess to qualify as participants, while exclusion criteria are attributes that would disqualify people from participating in your study.
The graphic below shows a comprehensive view of how population and sample are related.
Personal Project
Take a moment to think about target population, accessible population, sampling frame, and sample in the context of your own research. Start the thinking process broadly, identifying first your target population, and then slowly begin to narrow down to your sampling frame. Make some initial notes about accessible lists from which to select your sample. Then, think about where you may be able to find people who fit your inclusion criteria.