Recall this chapter's example of an organization conducting a random sample of 100 students from a college student population to learn about student preferences on different issues. Imagine the pollsters recruit participants using a random sampling method but get a disproportionate number of responses from some academic majors. Some majors are overrepresented relative to the student population and other majors are underrepresented. The following table shows the counts of different majors in the sample and in the general student population.

Respondent's Major Population Counts Sample Counts Political Science 160 25 Psychology 240 12 Biology 80 5 Engineering 320 16 English 100 7 History 160 13 Undeclared 540 37 Total 1,600 100