Colombo Telegraph

The Story Of Two Graphs Drawn By A Tamil Man

By Mahesan Niranjan

Prof. Mahesan Niranjan

At the famous Bridgetown pub yesterday afternoon, a Tamil man showed me two graphs he had drawn on beer mats. He is none other than Sivapuranam Thevaram, the Sri Lankan Tamil fellow who is my regular drinking partner. Statisticians among you might recognize the graphs as representing some kind of probability densities. Let me tell you the story behind these graphs.

Thevaram’s first graph was a simple one, widely known by the familiar phrase the “Bell Curve.” It represents how some stuff — like the price of onions in the Jaffna market — is distributed. Around where the graph peaks, you will find the price most of the time. Occasionally, say as a result of heavy rains leading to a bad crop, the price will be at the higher end of the graph. And at times, for instance, when Lalith Athulathmudali — the former trade minister in President Pinocchio’s evil government — decided to import onions in large quantities from India to “teach the Jaffna man a lesson,” you might have found the price at the lower end of the scale.

Now, the bell curve has famously been used to show how intelligence is distributed among a population. Some have used this to argue that there is such a natural distribution of the stuff and that if you were born at the lower end of it, there is nothing much you can do to redeem yourself. “It is all in the genes,” goes that particular theory, from which its proponents jump to the conclusion that certain ethnic groups are so well represented at the lower end of the spectrum that there is no point in investing any resources in their communities. These theorists are oblivious to the fact that the instruments to measure this inherited substance are designed in such a way as to put the instrument-maker at the advantageous end of the scale.

But to me, the bell curve is a useful tool in irritating my friend, Thevaram, particularly after his occasional visits to Sri Lankan universities. I would show him such a graph and use it to ridicule the level of scholarships in those institutions. “Not particularly developed are they – judging by the research they do and the average number of papers they publish – when compared to Oxford and Cambridge?” is my usual line of attack.

This annoys Thevaram immensely. Angrily, with beer froth dribbling on his unshaven chin, he would retort as follows:

“You have to know the context, machan (buddy).

“Just compare the student-staff ratios and contact hours for a simple explanation. Here at my university in Thatcherland, I teach six hours a week during term time. Someone with three times those contact hours, throughout the year, cannot keep publishing papers, can they? They will just be inundated with marking exam scripts throughout the year,” he would say.

“If scholarship in Sri Lankan universities is at the low end of the bell curve, machan, how come on every visit there, I happen to enjoy meeting rather clever people? I have conversations with them — over vadai and plain tea – which can be of the same intellectual calibre as the conversations I can have with Bridgetown folks — over scones and clotted-cream. You see?”

“Have you not come across sampling bias?” I would challenge his statistical methodology, triggering even more dribble of Peroni froth on his unshaven chin.

The above conversation on how the bell curve might map onto the intelligence in Sri Lanka, and its campuses, is something we have recycled over ten times in the last five years, and I am sure we are likely to repeat it in the coming years, too.

Today, however, we have something new. It is a curve my friend had drawn with two bells! Statisticians among you might recall the phrase “bi-modal” at the sight of this particular graph. Those versed in Tamil literature might even stretch their imagination and associate its use by poet “Ouvaiyaar” who wrote “iddaar periyOr idaathaar izi kulaththOr. [Those who give are great and those who don’t are no good] ”

Let me explain.

Unlike in the bell curve, which has only one “bump,” this one has two, an upper bump and a lower bump, with not much in the middle. If we take an average of the stuff of which we have drawn this graph, we will find there is nothing to represent that average in the middle. As such, unlike the average price of Jaffna onions, average intelligence may be a meaningless thing to talk about.

Get it?

If not, let me tell you a story.

Two economists from the World Bank went to offer advice to an African government. You know the drill: Sell off the railways, close down a few hospitals, privatize, privatize and privatize. The visit to the country is not necessary because it is the same advice on offer to everyone, but it comes as perks of the job. The duo went hunting one Saturday and came across a lion. The first one drew his gun, fired and missed, the bullet going a foot to the left of the lion. His friend, now in panic, pulled his gun and fired, also missing, with his bullet going a foot to the right of the beast. We can imagine what happened next, can’t we? The lion enjoyed a delicious lunch. Moments later, when they were queuing at the Pearly Gates, one said to the other: “On average, we got him!”

Get it now?

If not let me give you some news.

The Student Union of the Arts Faculty in the University of Jaffna, acting in the interest of preserving “our” culture, renewing an idea that initially came from their administration and later withdrawn, has decided to impose upon its members a dress code for attending lectures: Men shall not wear denim trousers or T-shirts, and shall have their shirts tucked in. Women shall wear saree on Fridays. Men shall not attend lectures sporting beards. The report claims the dress code will come into effect from 11 March 2016.

There is a law of nature our enthusiastic student unionists might discover, should they venture across the campus courtyard and explore the building marked “Library.”

A necessary condition for living in the comfort of the lower mode of Thevaram’s distribution — sketched on the Bridgetown pub beer mat — is the protection provided by elements of our culture, which no doubt we ought to preserve, and send our youth in their thousands to die for.

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