Norm_and_Criterion_Referencing

Norm Referencing The main purpose behind the use of norm-referenced assessment is to rank the performance of students in a particular group in order to generate a final grade. It involves fitting of the marks of students to a normal distribution (or 'bell curve') using a qualitative or statistical technique, allowing the assessor to re-interpret students' marks after the assessment has taken place (James, 2002). The resulting normal distribution is then used to allocate grades to students based on a pre-determined proportion of grades. This means that the quantity of each grade awarded to students can be standardised from year to year. The method of distributed grades in this fashion is based on the assumption that the performance of student groups is always roughly the same and can therefore be validly placed in such a normal distribution. This is an assumption that has been refuted by many authors (Bond, 1996; James, 2002, Shacklock & Morgan, 2000), yet despite this, norm referencing is still a very popular method of determining student grades in both secondary and higher education. Another criticism of the norm referencing method is that as the quantity of each grade that may be awarded is pre-set which does not adequately cater for student groups where there is either a very high or very low level of performance. A student that is awarded the highest grade in a course is assumed to have performed to a high standard, however, if the class as a whole had a poor level of performance, a person with the highest grade may not have performed as well as students awarded that same grade in previous years. Conversely, if a group of students has a very high level of performance, the norm referencing method means that only the same number of students as in previous years receive the top grade even though more students may have 'deserved' this grade on the basis of their outstanding knowledge and skills. The criterion referencing method involves "determining a student's grade by comparing his or her achievements with clearly stated criteria for learning outcomes and clearly stated standards for particular levels of performance" (James, 2002). By explicitly setting out the criteria for an assessment, this clarifies not only what is required of students but also assists instructors in determining what they need to teach. Criterion referencing can also improve the reliability of feedback offered to students as the criteria serve as points of reference for instructors to use when grading students' work (Knight, 2001, p.18). Unlike norm referencing, criterion referencing does not involve the allocation of marks to pre-determined distributions and therefore a student's mark is not influence in any way by the performance of other students in the course. This also allows for a greater ability to be able to compare the grades of students from different years, as the criteria is an objective reference point which is independent of the group being assessed. This method overcomes one of the problems of norm referencing by not allocating a fixed proportion of grades to a course. This means that as long as the criteria is met, it is possible for all students to attain a high grade, or in some cases, all students to fail. By more accurately reflecting the performance of the group rather than manipulating marks to a standard performance curve, criterion referencing is able to provide relevant feedback on the effectiveness of a course. If a high number of students are failing to meet the criteria and are therefore failing the course, it may indicate that the course needs to be redesigned to assist in the development of students' knowledge and skills. A high level of performance against the criteria could mean that the criteria may need to be reviewed or simply that the course is working well to achieve its learning objectives.