Chi-square test
Chi-square is a statistical test used on count data (i.e., categorical data). It can be used to find out if observed counts are different from expected counts.
For example: let’s say 50% of students walk to school. In grade 8, there are 100 students, so we would expect 50 of them walk to school. But when we asked them on a survey, 70 grade 8 students said they walk to school, and 30 said they do not. Is it just random chance that more grade 8 students walk to school, or is something else going on? A chi-square test could be used to answer this question.
See also: statistics