Norm-referenced and criterion-referenced assessments are two types of assessment in which results are specifically compared to something. Both are important in the assessment of students although they have very different purposes.
Norm-referenced assessment allows an instructor to compare a student's skills to others within a particular group and are most appropriate when the instructor wants to make comparisons across a large number of students or needs to make a decision regarding student placement and advancement. Norm-referenced assessments are better to use to determine individual performance in comparison to others.
