Let justice be done to our children

July 21, 2012, 3:19 pmA sinking ship in the mid seas calling for help is what reminds me of the latest debacle in the Z-score. The mess created by all what has happened will undoubtedly have many casualties in time to come. So the main objective and focus of all concerned at this juncture should be to minimize the damage and keep the potential casualty figure at its lowest.

I am dealing here with the ways and means of minimizing the suffering of those who sat the GCE A.L. in 2011, and are eagerly anticipating a speedy solution to their predicament. Hopefully, the committee appointed by the government subsequent to the Supreme Court ruling, will come up with a fair and just solution to assist all parties concerned- the students, parents and teachers. The purpose of this article is to look at the options available to devise a reasonable and rational scheme of admission based on the Z-score, under the present circumstances.

In finding a system that would be fair and rational, we first need to re-examine the two main methods of calculating the Z-score for the purpose of ranking students for university selection. Now, to grasp the underlying principle, let us just think of one subject in the A.L. examination. The simplest and straightforward method is to consider the marks of the two groups of students who sat the examination under the new syllabus and old syllabus as two distinct populations in the same subject. This is equivalent to treating the two groups of students as having sat for two different subjects.

The alternative is to disregard the change of syllabus and consider the marks of all students together though they represent two distinct populations, as has been done in the previous years when both new and repeat students sat for the same paper. Clearly, this alternative which is known as pooling of two different populations is valid only if the two papers are at the same level of difficulty (or easiness). If one paper is more difficult than the other, then the students of the group sitting for the difficult paper will undoubtedly be at a disadvantage. Apparently, the Department of Examination has assured that the setting examiners were specifically requested to maintain the same level of difficulty in the two papers, which fact has also been substantiated and corroborated by the members of the setting panels. So the alternative method of pooling of populations or considering all marks together and using suitable statistics, is also a valid option.

Now that we have two valid and acceptable methods, what we need to look at next is the consequence of using these two methods in ranking students for university selection. The best way to do this is to compare the percentages of first timers and repeaters who would qualify to gain admission to universities based on the two different methods, with past patterns of admission of the two groups of students. If we take a subject stream such as Medicine and compare past records of student admission under normal intake (40% merit) with projected figures for 2011 admission, under the two alternative methods, we will have the results shown in Table 1.

Table 1

Now, in examining the above figures carefully, we can clearly perceive a great injustice done to repeaters if we solely use the separate Z-score method for the purpose of ranking students for university admission. The percentage of repeaters (sat under old syllabus) who would qualify for university admission would drop drastically from a past average of 58% to 26%, while the percentage of first timers (sat under new syllabus) would increase significantly from a past average of 42% to 74%. On the other hand, if we look at the outcome of the pooled method, the figures are not only comparable, but are consistent with general trends observed during the past three years. The percentage of repeaters would increase marginally from a past average of 58% to 63%, consistent with a slow rising trend observed over the past three years, while the percentage of first timers would drop slightly from a past average of 42% to 37%, again consistent with a decreasing trend observed over the past three years. For visual illustration, this is represented in graphical form in the chart given below.

The above analysis could also be carried out for other streams as well, along the same lines. I have produced below the graphical results for the two streams of Engineering and Management under normal intake (40% merit).

Something that is quite evident in all three streams considered above is the fact that the direct application of separate Z-score method for the results of 2011 will undoubtedly place the repeating students in a very disadvantageous position. Unfortunately, unlike the first timers the repeaters are the ones who are going to be left with either just one more attempt or none at all, to recover and reclaim whatever legitimate right they have for gaining admission to a national university.

Thus it is quite evident that for the year 2011, the use separate Z-score method solely for the purpose of ranking students for admission to universities will cause great injustice to the repeating students. The disadvantage caused to repeaters by the application of separate Z-score method will have to be rectified by some other means that will provide redress to those who might potentially be dropped out from the repeaters. Any method that is going to be adopted will have to ensure that neither of the groups of students will have an undue disadvantage over the other in the final selection process. The committee appointed for the purpose of setting out a final scheme of selection will have to take into consideration the above facts if they wish to do justice and minimize the suffering of our students.

Dr. H. D. Goonetilleke,

The Open University of

Sri Lanka.