In general, international sporting success can be linked to national income (GDP per capita) and population size.
Put differently, look at the list of Olympic medal winners. Very often larger richer countries tend to do well, perhaps for two reasons. Firstly, they have the financial clout to dedicate resources to developing athletes (hiring costly overseas coaches, buying expensive equipment, building stadia and other facilities). Secondly, they have lots of people. More people should imply a bigger talent pool to choose from.
The combination should imply that richer countries produce more talented athletes, who can out-perform on the international stage and bring home the medals.
But what about RWC, does the same logic apply ? The answer is more nuanced – when as ever – we did our empirical testing.
What we found is that higher income countries are indeed more likely to be good at rugby union in general (compared to say very poor ones). However, in the select situation of the 20 teams in RWCs, GDP per capita did not make a difference. Why so ? Well perhaps its because wealthy countries such as the U.S., do not rank particularly highly in rugby.
In terms of population, the effect is also nuanced. Rugby is not particularly strong in India for example (which has a population of 1.3 billion people and is a world power in the sister sport of cricket). The four countries that have won RWC (Australia, England, South Africa and particularly New Zealand), are not hugely populated by international standards.
So we found that as regards RWC, GDP per capita had no effect, and having a higher population had a negative effect (i.e. bigger countries were less likely to do well).
Observation 3: national income did not affect success in RWC and the effect of population was negative.