To select a sample of 200 students, we need to identify all 10,000 students at the university. This may have suggested that we needed a larger sample size perhaps as many as 400 students. However, we could have also determined the sample size we needed using a sample size calculation, which is a particularly useful statistical tool.
This number was chosen because it reflects the limit of our budget and the time we have to distribute our questionnaire to students. Let's imagine that we choose a sample size of 200 students. If we were only interested in female university students, for example, we would exclude all males in creating our sampling frame, which would be much less than 10,000 students. Since we are interested in all of these university students, we can say that our sampling frame is all 10,000 students.
In our example, the population is the 10,000 students at the single university.
