Growing up in South Africa will no doubt mean that you have heard of, or played rugby in some form or another. For some, the memories might hold negative political connotations, while for others it brings back visions of grandeur and victory. Nevertheless, depending on your political stance, whether you played or not, or if you were in a winning side or not, rugby is entrenched in our society.
My own first experience was being thrashed by the then “Mighty” Queens College, while their supporters, intimidated us with the “Ingonyama” or “Inye Zimbini Zinthatho…” war cry. A harrowing experience if you were on the losing side.
Years later, my “Alma Mater”, Grey College, which is synonymous with school boy rugby, would hand back many of those defeats I experienced, to Queens. Today, however, my allegiance is completely split (in fact it's schizophrenic!). With a son at Bishops, I love watching their running style of rugby, but watching my friends’ and colleagues’ boys play with such passion for their opposing schools, I instantly become a huge supporter of Paul Roos, Paarl Boys and Bosch alike. The talent we have at school boy level in the Western Cape alone, leaves me very positive about the future of rugby in SA.
Being a rugby supporter can at times be very difficult, and being a supporter at school boy level, even more emotional than at national level (especially around a fire, when the Castles are flowing!). It was therefore with interest that we read and agreed with Mr Gustaf Pienaar, the then MIC Rugby and First XV Manager at Rondebosch Boys and current Deputy Headmaster, when he wrote about the issue of school boy rugby rankings (Bosch Blitz, 15 May 2013, 8th edition). Mr Pienaar states:
“I have always maintained that rankings are like someone patting you on the back and paying you a compliment: I accept it graciously and move on”.
For the most part we would agree with Mr Pienaar and “Hat Tip” to him for his pragmatic approach. The reality is that many of the rankings are opinion based to a greater or lesser degree and many do not carry much scientific basis. We were therefore delighted when MyComLink (www.mycomlink.co.za) asked us to see whether we could apply some science to the ranking, so as to remove the qualitative bias and make it a bit more quantitatively rigorous.
At NMRQL Research we love having fun with numbers and decided to see if there were existing ranking algorithms here in SA or overseas that could be applied. Ideally we were looking for something that would:
- Take into account wins over losses (naturally!)
- Not be biased in favour of schools which play more games.
- Would take into account the strength of the opponent.
- Would take into account draws between teams.
- Would not be skewed by home field or away field advantage, and
- Would not be biased by margin of win (WHAT! I hear you say?... more on this later)
So let’s have a look at each of these in no specific order of importance.