Saturday, February 16, 2013

Round Robin Results In The AFL NAB Cup

Currently, in the first round of the AFL NAB (pre-season) Cup, the 18 teams are split into 6 pools of three, and each pool of three plays each other within the course of a single night (e.g. last night Essendon played the Dogs, then the Dogs played Collingwood, then Collingwood played Essendon). On the way to breakfast this morning, Ms Wheatley suggested that I take a look at the NAB AFL Cup results and see what the results were like for ‘1v3, 2v3, etc…’

‘Damn it … ,’ I said, ‘Now I have to do that …,’

I did think of weaselling out of doing it by suggesting the topic to @AFLFootyMaths instead, but no, this was my burden to bear! Actually, it’s not much of a burden … since the round robin format only started in 2011 the sample size is just 13 pools.

For the purposes of the comparisons, team 1 in each pool is the team that plays in the first two matches of the night, team 2 plays in the first and third matches, and team 3 plays in the second and third matches.

1v2: 5 wins to team 1, 8 wins to team 2, net margin to team 1: -9 points.

1v3: 3 wins to team 1, 10 wins to team 3, net margin to team 1: -191 points.

2v3: 6 wins to team 2, 6 wins to team 3, 1 draw, net margin to team 2: +69 points.

So far, though team 1 has lost 8 out of 13 times against team 2, on point differential they have been fairly even (as one might expect). However, team 1 has fared relatively badly against the rested team 3, losing 10 out of 13 times, for a net margin of -191 points. This might indicate that team 1 is disadvantaged by having to play back-to-back matches, but again, it’s a small sample to date. In matches between teams 2 and 3, it’s all tied at 6 wins apiece (with one draw), but the net margin is 69 points in the rested team 2’s favour. Again, that might indicate a disadvantage from having to play back-to-back matches, but we might have to wait a few more years to get stronger evidence yet.


@AFLFootyMaths said...

First, if you would have offered for me to analyse, you would have got mocking laughter in return... The NAB Cup is a farce, and to considered as 'real football' as T20 matches are to cricket.

Second... Have you looked at previous years ladder positions or rankings in combination with the 'positions' of team 1, 2 and 3?
I suspect there is some seeding going on, dumping lower ranked (or even supported/sponsored) teams into the dead spot of Team 1.
Whereas the more highly rated (rating) teams get either later matches, or the break in game 2.

More research, Sir!

Troy Wheatley said...

Yes, I agree, the NAB Cup is a farce and this is the only time I shall blog about it.

I did think about controlling for the quality of teams, but well, I was just too lazy to do it. However, even if the lowly ranked team is getting dumped into the first two matches they appear to be performing better in the first match than in the second. But again - small sample.