Every year the Kenya National Examinations Council (Knec) standardizes the scores in the Kenya Certificate of Secondary Education (KCSE) examinations. KCSE Examination standardization is a mathematical process that is designed to remove variable elements from test scores and allow the candidates to be compared equally.
In other words, it is a way of giving equal value to the results of each test, regardless of the number of questions and the time allocated for completing them. For instance, an A in Mathematics is much lower than an A in History and Government. Read more here; The latest KCSE grading systems for all subjects.
Why Knec standardizes KCSE candidates’ Raw cores to Standard Scores
Standardization of raw scores to standard scores in a Knec examination is a process that involves adjusting the raw scores for each paper in the examination to allow for the differences in difficulty and in the extent to which scores scatter/ spread between the best and worst performing candidate (standard deviation).
In the process of standardization, the difficulty among the papers is measured in terms of mean raw scores obtained by the candidates, while the differences in scatter are measured in terms of the standard deviation.
A raw score is a mark that is obtained by a candidate before standardization. It is the original mark obtained by the candidate in a test i.e., the number of correctly answered questions.
For instance, if a candidate gets 90 marks out of 100 in a paper, then the raw mark for the candidate is 90. The mean raw score of a test is calculated by dividing the candidates’ total marks by the number of candidates taking the test.
The standard deviation of a score is measured by the number of units that score is from the mean score.
This process is done by using a computerized system.
In order to create a standardized score, a reference table called a ‘look-up table’ is created for each test paper that is written and the table is specific to that test paper because it takes account of the difficulty of the paper.
The minimum standardized score is derived from the look-up table and the actual number will vary, depending on the average score of all those taking the test.
The standard scores are a measure of relative performance and have the ability to tell us how a candidate has performed in comparison to the other candidates. These scores are essential when results from different papers must be combined to give an overall total as is the case in the KCSE examination and are useful for comparing relative performance of candidates from subject to subject or from year to year.
Once the raw scores have been standardized, the cut-off scores for Grade A to E are identical for all subjects and therefore maintained at the same level from year to year.
The standardized scores are then used for reporting candidates’ performance.
Does standardization affect the candidate’s position?
When the scores are standardized the relative positions of the candidates remain unchanged; the top candidate in each subject still remains at the top.
The standard scores are essential if scores from several examination papers are to be added to give a total score. It is therefore desired that each paper should contribute equally to the total score.
Standardized test scores are scores that are obtained from a test that is administered and scored in a consistent, or “standard” manner.
Standardized tests are designed in such a way that the questions, conditions for administering, scoring procedures, and interpretations are consistent and are administered and scored in a predetermined, standard manner.