Hello all,
first post on this forum.
Hoping in to share a few thoughts on the topic.
Mozart wrote:
Here are the facts:
Age<25 ....NZ 8....Boks 9
25<Age< 30....NZ 12...Boks 8
Age>30....NZ 11...Boks 14.
They might be facts but they are poorly chosen.
Correct brackets to study could be:
Players between 28 and 32, between 32 and 36, between 24 and 28.
The average age of a squad might be the best independent variable to measure the effect of age on team performance (you must look at the other independent variable to conclude)
The problem lies in that team performance depends on the yield of each position in the team and the performance at each position evolves differently with age.
So averaging on team age gives no reliable information.
Mental, physical and technical skills progress at a different rate and carry on differently (endurance drops less fast than acceleration for example)
It means that each position mature at a different age. Players are expected to reach their peak and go past their prime at a different age.
As an indication, we take that props mature at an older age (32) than wings(28)
Building a squad with two 32 props and two 28 wings contributes to the same average (30) than two 28 props and two 32 wings.
Except that one side fields four players in their prime while the other fields two players before their prime and two after their prime.
One side is expected to perform better than the other.
After a glance at wiki, it looks like NZ selection is closer to the first case (that is a line up of players in their prime) while SA is a closer to the second case (players past their prime and players who have yet to reach peak age)
This is a statistical approach and the SA selection might be composed of players all in their prime despite their age not corresponding with the average prime age for each position.