A research paper by Dr Ramaele Moshoeshoe from the National University of Lesotho (NUL) Economics Department has just won the Econometric Society Africa Region’s Young Economist Best Paper Award, beating competitors from the rest of Africa! As a reward, Dr Moshoeshoe has effectively booked his ticket as a Visiting Scholar to France, “I will be a Visiting Scholar to the Centre for Research in Economics and Statistics (CREST), in Palaiseau, France,” Dr Moshoeshoe said.
As a bonus, his paper will also receive a fast-tracked review by the prestigious Annals of Economics and Statistics journal.
Here is the story. The respected Econometric Society, a worldwide body promoting Econometrics, held its Africa Region international conference recently. There are several such region-specific conferences by the Econometric Society, “As an African scholar based in Africa, I submitted my paper to this Africa meeting of the Society.”
There was a competition in this section. Africa-based Economics Scholars within ten years of receiving PhD, who present at the conference would compete for the best research paper award. Scores of scholars from all over Africa presented.
Then came the good news!
“Well, I was just interested in sharing the findings of my paper and get feedback. As for my paper being considered the best, it came as a complete surprise!”
If you have been looking at the trend, NUL students and lecturers are going head-to-head, toe-to-toe, with their international peers and they are outcompeting them!
The economists amongst us are already salivating as they wait for an answer to this question, “what was this paper all about?”
Lesotho introduced free primary education (FPE) many years ago, in 2000, and phased it in grade-by-grade. In 2012, the first cohort that benefited from this policy since it was introduced entered the NUL. What does the available data show about its performance? Was their performance better or worse than that of students who came before them, and who never experienced FPE policy?
That’s a hard nut to crack.
The first question is, why would an economist be interested in the first place? Well, economists are interested in development, and human capital is critical for development. Thus, knowing how government policies impact human capital development is a preoccupation of economists all over. This is because how well people are trained and educated determine how productive they will be in the economy.
“We used a method called Difference-in-Differences to find the long-term impact of the said policy,” the Dr said.
At NUL, students’ academic performance is based on their year averages (Overall Weighted Average or OWM). So these OWMs were used to determine the long-term impact of the free primary education policy on the student’s performance at the NUL.
In its simple form, the Difference-in-Differences method goes this way.
“We subtract the OWM of students who were in their second-year from the OWM of first-year students at NUL in 2012.” Second-years were not affected by FPE in 2012. A little bit of mathematics will make it clearer.
[OWM_f – OWM_s ]^2012,
where (f) is first year and (s) is second year and 2012 is the year the students did their first year.
“Then we subtract the OWM of students who were in their second-year from the OWM of first-year students at NUL in 2010 and 2011 before FPE.”
[OWM_f – OWM_s ]^(2010-2011)
“Then we take the Difference of the Differences.”
[OWM_f – OWM_s ]^2012 – [OWM_f – OWM_s ]^(2010-2011)
If the Difference of the Differences is at or closer to zero, this would mean FPE policy did not have an impact, negative or positive. However, if the difference is either significantly positive or negative, then the policy has some impact.
For this approach to make sense, “we had to assume that the Difference of the Differences for the years prior to 2012 were not changing and our statistical checks on the available data said as much.”
When they applied the Difference-in-Differences, they had to ensure that they were comparing apples to apples. For instance, whether the performance by the 2012 group had improved or decreased compared to previous year could be a matter of whether the university, in 2012, selected only the best students from high school, because there was a huge number of students graduating from high school, or a host of other reasons.
“We had to check all such factors.”
So the students were compared faculty to faculty, gender to gender, district to district, age-cohort to age-cohort, and by family wealth.
The free primary cohort performed better than those who came before them by a margin of 4%.
“We don’t have enough data to make conclusions,” Dr Moshoeshoe said. However, he said the available data shows the following things happened during the policy implementation. (1) Lesotho’s FPE policy was implemented one year at a time, it was not a Big Bang, as it happened in other countries. (2) This afforded government time to build more schools and (3) increase the number of teachers, which, according to the available data, led to a sharp decrease in student teacher ratio and (4), during the same period, there was an increase in teacher qualification.
All these have been shown to positively affect student learning, and could have contributed.