This is a post on tournaments and tournament design.
Economists and statisticians have loved tournaments for many years. For example, many years ago two American labour (work) economists were trying to explain why a CEO’s pay jumps hugely the day they are appointed. How could someone’s marginal product jump so much, so quickly. The solution to the puzzle came from sports. If one thinks about the race to become CEO as a promotion tournament, then the jump in remuneration as the “prize”, it all starts to make much more sense. Interestingly, this was done before sports economists had started thinking about tournament structures and incentive devices (which they subsequently have quite intensively).
Jumping on to sports tournaments. A crucial point to bear in mind is that they can be designed in many many ways, depending on the particular circumstances (e.g. purely domestic or international setting) and what the tournament organiser’s are trying to achieve (think about the World Series in Baseball as an example, or the FA Cup in football, quite different structures).
Lets take an extreme and stress purely hypothetical example to show the point. Suppose an omnipotent designer was only motivated by pure self interest. Well they could easily design a tournament such that their team only played against weak teams all the way to the final (which would be played at their home ground, with no away fans allowed in). Clearly that would push their win probability up hugely. Somewhat un-realistic yes. But it highlights that a tournament designer has many options and levers they can deploy.
RWC’s tournament format has been broadly un-changed since 1987 (yes the number of teams increased over time from 16 to 20 but the basic structure has remained the same). It can be categorised as an international, hybrid, multi-stage, single elimination tournament. Lets de-compose the technicality.
The participants represent their national rugby unions – so it is an international tournament (as an aside, thus creating the context for the research work we have done on trying to link tournament success to national fundamental characteristics such as geography and socio-economics).
It is a hybrid format in the sense that it contains two sub-formats: the opening round robin pool stage, and then the single elimination (or knock-out) phase.
It is a multi-stage tournament – in fact there are four stages: pools, quarter-final, semi-final, and final.
Single elimination is the tough part. Un-like other tournaments, there is no consolation or ‘back-door’, other than the bronze final for third and fourth place – so it is ‘single’. Elimination means that upon the completion of each stage, there is no tomorrow, teams either advance or they go home. Its quite a tough format really.
Observation: adding the above up, from a tournament design perspective, RWC can be seen as an international hybrid multi-stage single elimination tournament.