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Restaging Z-Score Debacle



The release of the Z scores for university admission by University Grants Commission (UGC) has brought thousands of complaints and issues from the students, parents, teachers and other stakeholders into discussion. Some others have vowed to take the issue to courts, expecting a fair and just solution.

Most of the complaints are related to the issue of two different cutoff Z scores for new syllabus and old syllabus and comparisons thereof. It is understood that the solutions proposed to resolve a crisis must not only be fair and legal but also seen to be reasonable for the stakeholders. Print media during the last couple of weeks published several opinions on this issue and the use of Z score for university admission is often blamed as the reasons for these discrepancies. It is time we had a closer look at the problem and baseless allegations against the use of Z-score for university admission. The use of Z-score in place of aggregated marks of the three subjects is, by all means, a better method, which has been amply demonstrated with data and examples and subjected to discussion since its introduction for university admission in 2003.

There is a diverse degree of variability in nature itself and so it is with the humans and their work. The scientific discipline called statistics provides the conceptual and procedural approaches to understand the variability and manage it fairly and equitably. Due to the inherent variability present in question papers and evaluations, it is very well understood that the simple aggregate obtained from the marks of different subjects is not a fair criterion for determining the eligibility for university admission. The degree of difficulty of the question papers in different subjects varies significantly and also there are variations of the aptitude measurement scale in different years. Therefore, it was not possible to have a fixed cut-off mark or simple aggregate solution to determine eligibility for university admission. For example, marks for one subject could have a range from 5 to 70 while the range for another subject spans from 45 to 99. A student who obtained 70 is the best among the lot in the first case and the one who obtained 70 in the second case is a mediocre student. When the simple aggregate is taken as the criterion for university admission, the best student in the first case is treated equally with the mediocre student who opted for a relatively easy subject as in the second case. Within the general assumption that students who sit for these two different subjects have a more or less equal level of competence, the disparity in the relative difficulty of the question papers or evaluation criteria warrants some sort of an approach for standardization. This issue was the theme for a series of discussions in academic circles and despite several advanced methodologies available for standardization, the Z score approach was adopted about 20 years back as the criterion for university admission due to its simplicity, computational convenience, application efficiency and the need for only two parametric estimates for its calculation.

Today, the issue is somewhat different and it is not possible to assume that the students who sat for two different papers in the same subject are having a more or less equal level of competence or they are random picked from the larger population. The first group has sat for the examination for the first time and the other group has at least attempted to pass the examination on one or more previous occasions. This is evident from the number of the first, second and third attempt students in different disciplines. In exploring a solution to this present problem, the underlying assumptions made in calculating the Z score rankings need to be reexamined. One of the assumptions is that the aptitude of knowledge and skills of the student population opting for different subjects or subject streams are not significantly different. This assumption should be validated now because almost all the students who sat the examination under the old syllabus except those with valid medical or other reasons have made a failed attempt to enter university earlier. 

Those who qualify from the new syllabus are a group of students who took the examination for the first time. The assumption of equal knowledge and similar competency level and skill background for these two diverse groups introduces an error into the fair selection process. It is not possible to issue a single series of Z-scores for these two groups. Before processing marks, the hypothesis of statistically non-significant difference between these two student groups needs to be validated with at least past data for a period of 5 years. Since this hypothesis cannot be proved, then the degree of dissimilarity needs to be assessed to determine a fair ratio for university admission from these two groups of students and design a quota for these two groups. This is what the UGC has attempted to employ in the selection process, however, higher differences in the cut-off Z scores due to the impact of quota applied for the two groups has led to serious doubts in the mind of those without an in-depth knowledge of the method.

The second issue is whether the relative difficulty of two questions papers in both old and new syllabi is significantly different. The expert opinion is the only choice we have in this decision. If experts believe that the two sets of questions papers are of more or less a same level of standard, then the two results could have been combined into a single data series with only one set of Z scores and cut-off marks. Unfortunately, there is no evidence to show that this option had been explored by the UGC. If the question papers are at significantly different standards, then it is not possible to combine the two results series. Then the question must be asked from the Department of Examinations why the standards were made to be different and a strong justification for such an action. We always advise our students that they should propose a valid statistical methodology before they collect their data for research to ensure the compatibility of data with the statistical techniques to be employed in the analysis. Unfortunately, the Department of Examinations could not stick to this advice and only seeks a statistically valid solution after collecting the data from student examinations.  

Without understanding the pertinent facts, some argue that the mistakes made in 2011/12 university admission have been repeated in releasing the Z-scores for 2019/20 university admission. A similar problem indeed arose in 2011/12 admission due to the release of Z scores, combining the results of students who followed the GCE Advanced level under old and new syllabi. However, in 2011/12 university admission, the major issue was the errors made in the calculation of Z scores by the Department of Examinations. That mistake was further complicated due to the release of a single Z score combining the two distinctly different student populations of old and new syllabi as a single group by the UGC. A presidential expert committee was appointed to look into the problem and the mistake in the calculation was quickly identified and corrected. Besides, the need to consider the two student populations of old and new syllabi separately for university admission was proposed and it was later approved by a Supreme Court judgment in a case filed by a group of aggrieved students. 

There are few solutions which could have been adopted to avoid the complexity of the problem and misunderstanding among the students, parents and teachers:

a) The easiest approach would have been the designing one question paper for both groups of students sitting the examination under both old and new syllabi giving options to select questions from the areas that had been revised or amended in the new curriculum. It is observed that there have been no major deviations and only minor changes have been made as regards Physics and Chemistry. The relative difficulty level needs to be maintained across all optional questions. Then, it is a single question paper and a single Z score series generated from the results. This should have been achieved at the point of setting of question papers by the examiners with clear instructions.

 b) if the two questions papers, although structurally different, are of the same level of difficulty, the results of the two examinations could have been combined and Z scores computed as a single series. 

This solution could have been explained to the Supreme Court and concurrence on this approach sought. 

It could have been assumed that although the student populations were different, the same level of tests had been administered for both groups and therefore,

c) The most reasonable solution for the problem is to determine the ratios of students admitted to universities for each subject stream and each degree programme separately for old and new syllabus students, and then for each case use the five-year maximum proportion to admit students to universities. Then the total would exceed one hundred since the maximum of both ratios would exceed 100 and a small proportion of students needs to be admitted to each degree programme to avoid any obvious injustice. The use of median value can also be adopted unless there is a positive or negative trend in the ratios. If the five-year values are stationary and have a low variability among years, this becomes a fair solution. In case the five-year values are having a higher degree of variability and an obvious trend, the most recent value should have been the choice. This method of median value was adopted this year and due to the quota being significantly different for different disciplines and degree programmes, the cut-off Z scores have shown many differences for new and old syllabi students. Also, the cut-off Z-scores are significantly high compared to the figures of the previous years due to the application of quota which sometimes 25% of the original 100. This is the reason for the complaints although the method used for selection is in keeping with the ruling of the Supreme Court in 2012.

However, this problem could have been avoided if the two series of Z scores were adjusted as per the quota granted for each series. A simple mathematical computation could have brought the two distributions on a comparable model. The adjusted Z scores are comparable with the figures of the previous years and it would not produce cut-off Z scores which are much different for students in two groups. The confusion created due to the releasing Z scores indicating a different level of access to university entrance in the two different groups could have been avoided with the help of such an approach.


The writer is Former Vice-Chancellor of the Uva Wellassa University and Chairman of the UGC University Admission Committee in 2013/14 and member of Presidential Committee on Z score in 2012 .

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Govt.’s choice is dialogue over confrontation



By Jehan Perera

Preparing for the forthcoming UN Human Rights Council cannot be easy for a government elected on a nationalist platform that was very critical of international intervention. When the government declared its intention to withdraw from Sri Lanka’s co-sponsorship of the October 2015 resolution No. 30/1 last February, it may have been hoping that this would be the end of the matter. However, this is not to be. The UN Human Rights High Commissioner’s report that will be taken up at the forthcoming UNHRC session in March contains a slate of proposals that are severely punitive in nature and will need to be mitigated. These include targeted economic sanctions, travel bans and even the involvement of the International Criminal Court.

Since UN Secretary General Ban Ki-Moon’s visit in May 2009 just a few days after the three-decade long war came to its bloody termination, Sri Lanka has been a regular part of the UNHRC’s formal discussion and sometimes even taking the centre stage. Three resolutions were passed on Sri Lanka under acrimonious circumstances, with Sri Lanka winning the very first one, but losing the next two. As the country became internationally known for its opposition to revisiting the past, sanctions and hostile propaganda against it began to mount. It was only after the then Sri Lankan government in 2015 agreed to co-sponsor a fresh resolution did the clouds begin to dispel.

Clearly in preparation for the forthcoming UNHRC session in Geneva in March, the government has finally delivered on a promise it made a year ago at the same venue. In February 2020 Foreign Minister Dinesh Gunawardena sought to prepare the ground for Sri Lanka’s withdrawal from co-sponsorship of UN Human Rights Council resolution No 30/1 of 2015. His speech in Geneva highlighted two important issues. The first, and most important to Sri Lanka’s future, was that the government did not wish to break its relationships with the UN system and its mechanisms. He said, “Sri Lanka will continue to remain engaged with, and seek as required, the assistance of the UN and its agencies including the regular human rights mandates/bodies and mechanisms in capacity building and technical assistance, in keeping with domestic priorities and policies.”

Second, the Foreign Minister concluding his speech at the UNHRC session in Geneva saying “No one has the well-being of the multi-ethnic, multi-lingual, multi-religious and multi-cultural people of Sri Lanka closer to their heart, than the Government of Sri Lanka. It is this motivation that guides our commitment and resolve to move towards comprehensive reconciliation and an era of stable peace and prosperity for our people.” On that occasion the government pledged to set up a commission of inquiry to inquire into the findings of previous commissions of inquiry. The government’s action of appointing a sitting Supreme Court judge as the chairperson of a three-member presidential commission of inquiry into the findings and recommendations of earlier commissions and official bodies can be seen as the start point of its response to the UNHRC.





The government’s setting up of a Commission of Inquiry has yet to find a positive response from the international and national human rights community and may not find it at all. The national legal commentator Kishali Pinto Jayawardene has written that “the tasks encompassed within its mandate have already been performed by the Lessons Learnt and Reconciliation Commission (LLRC, 2011) under the term of this President’s brother, himself the country’s Executive President at the time, Mahinda Rajapaksa.” Amnesty International has stated that “Sri Lanka has a litany of such failed COIs that Amnesty International has extensively documented.” It goes on to quote from the UN High Commissioner for Human Rights that “Domestic processes have consistently failed to deliver accountability in the past and I am not convinced the appointment of yet another Commission of Inquiry will advance this agenda. As a result, victims remain denied justice and Sri Lankans from all communities have no guarantee that past patterns of human rights violations will not recur.”

It appears that the government intends its appointment of the COI to meet the demand for accountability in regard to past human rights violations. Its mandate includes to “Find out whether preceding Commissions of Inquiry and Committees which have been appointed to investigate into human rights violations, have revealed any human rights violations, serious violations of the international humanitarian law and other such serious offences.” In the past the government has not been prepared to accept that such violations took place in a way that is deserving of so much of international scrutiny. Time and again the point has been made in Sri Lanka that there are no clean wars fought anywhere in the world.

International organisations that stands for the principles of international human rights will necessarily be acting according to their mandates. These include seeking the intervention of international judicial mechanisms or seeking to promote hybrid international and national joint mechanisms within countries in which the legal structures have not been successful in ensuring justice. The latter was on the cards in regard to Resolution 30/1 from which the government withdrew its co-sponsorship. The previous government leaders who agreed to this resolution had to publicly deny any such intention in view of overwhelming political and public opposition to such a hybrid mechanism. The present government has made it clear that it will not accept international or hybrid mechanisms.





In the preamble to the establishment of the COI the government has made some very constructive statements that open up the space for dialogue on issues of accountability, human rights and reconciliation. It states that “the policy of the Government of Sri Lanka is to continue to work with the United Nations and its Agencies to achieve accountability and human resource development for achieving sustainable peace and reconciliation, even though Sri Lanka withdrew from the co-sponsorship of the aforesaid resolutions” and further goes on to say that “the Government of Sri Lanka is committed to ensure that, other issues remain to be resolved through democratic and legal processes and to make institutional reforms where necessary to ensure justice and reconciliation.”

As the representative of a sovereign state, the government cannot be compelled to either accept international mechanisms or to prosecute those it does not wish to prosecute. At the same time its willingness to discuss the issues of accountability, justice and reconciliation as outlined in the preamble can be considered positively. The concept of transitional justice on which Resolution No 30/1 was built consists of the four pillars of truth, accountability, reparations and institutional reform. There is international debate on whether these four pillars should be implemented simultaneously or whether it is acceptable that they be implemented sequentially depending on the country context.

The government has already commenced the reparations process by establishing the Office for Reparations and to allocate a monthly sum of Rs 6000 to all those who have obtained Certificates of Absence (of their relatives) from the Office of Missing Persons. This process of compensation can be speeded up, widened and improved. It is also reported that the government is willing to consider the plight of suspected members of the LTTE who have been in detention without trial, and in some cases without even being indicted, for more than 10 years. The sooner action is taken the better. The government can also seek the assistance of the international community, and India in particular, to develop the war affected parts of the country on the lines of the Marshall Plan that the United States utilized to rebuild war destroyed parts of Europe. Member countries of the UNHRC need to be convinced that the government’s actions will take forward the national reconciliation process to vote to close the chapter on UNHRC resolution 30/1 in March 2021.

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Album to celebrate 30 years



Rajiv Sebastian had mega plans to celebrate 30 years, in showbiz, and the plans included concerts, both local and foreign. But, with the pandemic, the singer had to put everything on hold.

However, in order to remember this great occasion, the singer has done an album, made up of 12 songs, featuring several well known artistes, including Sunil of the Gypsies.

All the songs have been composed, very specially for this album.

Among the highlights will be a duet, featuring Rajiv and the Derena DreamStar winner, Andrea Fallen.

Andrea, I’m told, will also be featured, doing a solo spot, on the album.

Rajiv and his band The Clan handle the Friday night scene at The Cinnamon Grand Breeze Bar, from 07.30 pm, onwards.

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LET’S DO IT … in the new normal



The local showbiz scene is certainly brightening up – of course, in the ‘new normal’ format (and we hope so!)

Going back to the old format would be disastrous, especially as the country is experiencing a surge in Covid-19 cases, and the Western Province is said to be high on the list of new cases.

But…life has to go on, and with the necessary precautions taken, we can certainly enjoy what the ‘new normal’ has to offer us…by way of entertainment.

Bassist Benjy, who leads the band Aquarius, is happy that is hard work is finally bringing the band the desired results – where work is concerned.

Although new to the entertainment scene, Aquarius had lots of good things coming their way, but the pandemic ruined it all – not only for Aquarius but also for everyone connected with showbiz.

However, there are positive signs, on the horizon, and Benjy indicated to us that he is enthusiastically looking forward to making it a happening scene – wherever they perform.

And, this Friday night (January 29th), Aquarius will be doing their thing at The Show By O, Mount Lavinia – a beach front venue.

Benjy says he is planning out something extra special for this particular night.

“This is our very first outing, as a band, at The Show By O, so we want to make it memorable for all those who turn up this Friday.”

The legendary bassist, who lights up the stage, whenever he booms into action, is looking forward to seeing music lovers, and all those who missed out on being entertained for quite a while, at the Mount Lavinia venue, this Friday.

“I assure you, it will be a night to be remembered.”

Benjy and Aquarius will also be doing their thing, every Saturday evening, at the Darley rd. Pub & Restaurant, Colombo 10.

In fact, they were featured at this particular venue, late last year, but the second wave of Covid-19 ended their gigs.

Also new to the scene – very new, I would say – is Ishini and her band, The Branch.

Of course, Ishini is a singer of repute, having performed with Mirage, but as Ishini and The Branch, they are brand new!

Nevertheless, they were featured at certain five-star venues, during the past few weeks…of their existence.



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