Kids with tuition fare worse. REALLY??? [Opinion]

Kids with tuition fare worse screams another rubbish article in the local paper.

Another week and another newspaper article to debunk.


They have been on a vendetta against the tuition industry due to how big the sector is.


And it is definitely a slap in the face to the Education Ministry if students are consistently seeking out tuition.

Kids with tuition fare worse: the arguments for

So the author, a lecturer at the department of economics at NUS compared retrospective data collected in 2012 of Singaporean student performance in PISA. This is also known as the Program for International Student Assessment and as such he determined that students with tuition fared worse.

Kids with tuition fare worse: debunking it

Readers mention about how inappropriate statistical analysis of the article is.


Since this makes the article appear silly, it have been taken offline.


Instead I will comment about the methodology from a clinical trials perspective. As such make it relevant to biology (since I am a H2 BIO tutor).


Clinical trials are always prospective studies.


Meaning when identifying a novel treatment, design a trial, start enrolling patients and then collect data off them.


Do an analysis subsequently, back it up with statistics and then come to a conclusion. Is it useful or not?


Nobody will do a clinical trial backwards (retrospective).


That is go back to the medical records analyze their situation and come to a conclusion the usefulness of a new drug or existing treatment.

The nuts and bolts

The main reason for that is because the more analysis uses the same set of data the more likely one will find a relationship between an independent and dependent variable.


In this case whether students having take tuition or not and their score in PISA.


If there is a correlation, this may not be because the relationship is true but rather a chance finding.


Just like if a person keep buying TOTO or 4D or lottery tickets, over a period of time there will be a chance that person will make a correct guess and eventually win something.


Then is it because the person is lucky or is it because the person has a deep insight and resulting in a correct guess?


Also, retrospective studies are very biased and cannot be controlled.


Nobody can make causative conclusions from such studies (like what the lecturer did) and can only point out possible correlations.


This in turn needs to be confirmed with prospective studies. Why are retrospective studies biased? Let me give you one example.

Explaining bias

PISA is not a universal test ALL students in Singapore take.


Therefore the sample collection is not representative of the students in Singapore and their performance relative to whether they go tuition or not.


Take a top tier Independent Singaporean school for example, between PISA and MENSA or the Olympiads, the latter 2 are more prestigious and time is spent preparing for it.


PISA is then left to government schools. Can you see how that will skew the results?


If the author is serious about the comparison, then design one prospective study, randomized and double-blinded.


Then see what the results conclude.


This is how proper research can yield amazing insights.


However, with the slipshod work and reportage it reflects badly not only on the paper but also on the professor himself.


Just so that they can disparage the tuition industry…


So if his point is valid, he should conduct a proper study. Unfortunately, they will only serve to debunk his view that kids with tuition fare worse.

Kids with tuition fare worse: bottomline

By the way, it is not uncommon for tuition centers to brag about their students achieving gold for Olympiads (scroll to the bottom of the page).


At the same time, may I also point the author to the article mentioning the top performance of PISA in Singapore due to tuition!


That article directly contradicts his stance.


So which is which?


I hope in this short exercise, I bring to the surface the importance of analytical skills.


This is something I routinely teach so that they begin to do better in application questions.


Finally, let me know if this has been useful.