Experts want wide, careful consultation on Z score formula; No fault in answer script evaluation
The expert committee, appointed by President Mahinda Rajapaksa to probe the 2011 GCE (A/L) examination results mix-up, has said in its report that given the reliance of the UGC on the results of the A/L examination for University admission, the formula to be used in determining the common indicator (the use of the z score calculation) should be decided by the University Grants Commission after careful and wide consultations.
The report has been submitted by a committee of learned persons comprising the Secretary to the Ministry of Technological Research Mrs. Dhara Wijetillake (Chairperson) Vice Chancellor of the University of Colombo, Prof Mrs. Kshanika Hiriburegama, Vice Chancellor of Moratuwa University Prof. Ananda Jayawardena, Vice Chancellor of Uva Wellassa University Prof. Ranjith Premalal De Silva and the Principal of the Royal College Mr. Upali Gunasekara.
The other findings of the committee are as follows according to a media release issued by the President’s office:
The error in calculating the district rankings had been caused at the last stage (processing stage), and not at the stage of entering data.
This processing error had been rectified by the Department of Examinations within a short period of time and the results released thereafter do not contain inaccuracies due to this processing error.
The officers responsible had not taken adequate steps to avoid the causes that contributed to the error.
An independent process Audit should be carried out to provide for continuous improvements of the entire examination process. This should ideally be carried out by the Ministry of Education.
Inquiries conducted regarding the specific appeals made by the candidates in response to the public call by the Committee have been examined. The Committee has found that there are no processing errors in those results.
There is a need to take several steps to enhance the capacity of the department to handle the technology related functions of the department. The Committee has identified what these are, specifically.
As an immediate measure, the services of a Consultant should be obtained to provide advice on technology related matters.
Matters relating to software improvements should be examined. In particular, every revision of a computer programme and data processing, should be double checked, verified and validated before implementation.
Implementation of recommendations of previous Committees as well as this Committee, should be ensured through an Action Plan with time targets for implementation. This should be monitored by the Ministry of education.
The cadre and financial provision required by the Department of Examinations should be provided to ensure optimum efficiency.
Complaints with regard to the 2011 G.C.E A/L examination should be addressed by the department with extra concern and caution to restore the credibility of the department. A special help line should be established to receive all the complaints and these should be responded to.
Courtesy: The Island
Expert committee recognizes that fault is in the method used to combine and pool data to calculate Z score. Prof. Raphel O. Thattil also recommends calculation of z scores separately.
“The solution is to consider the 2 groups as 2 different populations and calculate the Z score for each group separately using the (un-pooled) mean and variance for each subject. The average of the Z scores of the 3 subjects can then be taken to obtain the ranks. This solution is simple and elegant.”
Department of examination can easily calculate z score separately within few days and release accurate results.
Any student can easily calculate and show in courts that average Z score value is wrong by using un-pooled mean standard deviation and raw marks for each paper in respective syllabus.