Analysis Effect of new rules on scores round 1 - 10

[Foley#41]

There have been 90 games so far this year for a total of 180 scores.
To the end of round 10 last year there were 89 games, as Suns & Power had a bye in round 10 to allow time to clear customs in China.

The average score for all teams to round 10 this year has been 80.4 points.
The average score to round 10 last year was 83.1 points.

Now this might seem like a drop in scores, but a simple statistical analysis (2-tailed Student t-test for those who care) shows that these two numbers are not statistically different (p=0.28*). That is to say, statistically that difference in numbers could be just due to random variation and do not represent a meaningful change in either direction.
Conclusion: average score for all games is no different to last year. Not lower, but not higher either.

WTF you might say. Surely scoring has been lower this year.
Well not on average it hasn't. However....
If you look at the average score for winning teams there has been a drop.
2018 average winning score: 99.8
2019 average winning score: 93.9
That does represent a significant fall (p=0.040), so the average score for winning teams has fallen.

What about average score for losing teams? Well, that hasn't changed at all:
2018 average losing score: 66.3
2019 average losing score: 66.9
Not surprisingly, these are statically the same (p=0.83). Average losing scores are unchanged.

Now, since the winning score has fallen but the losing score is the same, that must mean the games are closer right?
Well actually it does. The average margin has fallen so far this year:
2018 average margin: 33.4
2019 average margin: 27.0
These are (just) statically significant (p=0.049), meaning that the margin this season is really lower than last season. The difference may not be meaningful in your mind but has change a bit.
Want more proof that games are closer? Well, the number of games decided by less than two goals and less than one goal has also risen:
2018 margin < 12 points: 15 games —- 2018 margin < 6 points: 7 games
2019 margin < 12 points: 20 games —- 2019 margin < 6 points: 15 games

In summary:
For the first 10 rounds of the season, compared to the first 10 rounds of 2018, the average score has not changed but the games are closer.

Now, it's not possible to say why this has happened. Certainly the new rules have not increased scoring to this stage, but they probably haven't wrecked the game in the way that some people, including me, thought they would.
If you have any questions, or would like any further analysis, I'd be happy to have a look (within the limits of my basic statistical abilities).

*I've included the p values for those who are familiar with statistical analysis. Essentially, if the p value is < 0.05 it means that there is less than 1 in 20 chance that the difference in numbers is due to random variation, a commonly accepted cutoff for a real (rather than a random) difference.

 

[Supercoach Bargain]

Stop putting facts in the argument.
The new rules are killing the game I tells ya.

 

[SportsCentre]

I've not been in the "new rules have affected the game" camp.
I like 6-6-6 personally.

My question would be how many scoring shots are we seeing now?


But what I did do a double-take on was something Jack Riewoldt said during a broadcast today.
He was asked how many shots on goal he would take at training each week, and not only did he reply with "about 40", he said "allowed to take about 40" so if he trained 3 times a week, the 3 time Coleman Medalist is taking 12-13 shots at goal per training session, and we wonder why players miss from 20m out constantly. Scoring would probably have increased if players kicked the goals they should.

 

[Milanista28]

To my eye the game looks exactly the same to me. I still like it.

 

[D-N-R]

There are also fewer easy beat teams this year. Brisbane, St Kilda and Gold Coast are more competitive. This is more likely natural progression than anything to do with the rules.

Best measure would be goals scored after centre Bounces - within say 30 seconds. Or goals scored from kick-outs.

If the new rules haven't made any change to the game you might think that it's OK. But if they haven't made any difference, then we should ask if they are needed? Why have them if nothing changes?

 

[the harry]

There are also fewer easy beat teams this year. Brisbane, St Kilda and Gold Coast are more competitive. This is more likely natural progression than anything to do with the rules.

Best measure would be goals scored after centre Bounces - within say 30 seconds. Or goals scored from kick-outs.

If the new rules haven't made any change to the game you might think that it's OK. But if they haven't made any difference, then we should ask if they are needed? Why have them if nothing changes?

Was going to post much of the same, although not as well worded or structured.

 

[sobrave]

To my eyes the game is almost unwatchable this year and frequently we're now having games where one team is basically not scoring in the first half. Scores are ramping up in the last quarter when players are tired and the leading team switches off.

Of course, it could be since I'm watching mainly port games and our game style resembles an octopus trying to cook a three course meal

 

[BIRDBRAIN]

If the new rules haven't made any change to the game you might think that it's OK. But if they haven't made any difference, then we should ask if they are needed? Why have them if nothing changes?

Exactly, all they have done is make the game even more complicated and difficult to umpire for no benefit to the game at all.

 

[sprockets]

The final scores might be closer but what about during the game? Maybe teams are taking their feet off the pedal towards the end of games more this year, like the Tigers did against the Bombers. That game wasn't as close throughout as the final scores suggest and it was always going to be a comfortable Tiger victory.

 

[The_Eagles]

It feels like there are whole quarters almost with no goals, and then 4-5 each the next

I don’t really care about “bring back the 10 goal full forward”
What’s so much more exciting about a lead and marking guy ?

 

[iluvparis]

What is the median score this year compared to the same stage last year?

Ron The Bear

 

[Foley#41]

What is the median score this year compared to the same stage last year?

Ron The Bear

The median team scores are 82 points for 2018 and 77 points for 2019.
The median game totals are 165 points for 2018 and 158 points for 2019.

 

[Andrew Mc]

To my eye the game looks exactly the same to me. I still like it.

I think it looks much better without runners. Best thing they've changed for some time.

 

[Foley#41]

Here is a ladder of teams ranked by change in average score compared to 2018 (rounds 1 - 10) from best to worst.
There seems to be a wide scatter compared to current ladder position, so clearly some teams are coming off a very low baseline (Carlton, StKilda) whereas the opposite is true for Melbourne. Obviously there may be many reasons for a change in a team's fortunes other than just the change in rules.

 

[inbetween]

Before even entering the thread or reading the OP. I was going to guess that there had been absolutely little to no change in overall scoring.
It's actually an indictment on those who manage the game. That their rule changes have no impact whatsoever.

 

[NoobPie]

Before even entering the thread or reading the OP. I was going to guess that there had been absolutely little to no change in overall scoring.
It's actually an indictment on those who manage the game. That their rule changes have no impact whatsoever.

No it's not. It's indictment on the broad stupidity of the whingers around here

No-one ever said increasing scoring was the primary objective of the rule changes. No-one guaranteed that everything would work absolutely

The data apparently suggests that scoring has increased after centre bounces and that the game is opened up for up to 60 seconds afterwards

The data apparently suggests no impact around the kick in changes. But it is too soon surely to confirm whether or not the coaching response has been overly focussed on defending these new rules rather than exploiting them

On that note, it is too early to tell whether dominant coaching strategies have dominated any positive (in terms of scoring) impacts due to the rules.

My take is the games seem to be relatively more open/posession based rather than territory / congestion based which has little to do with any rule changes

But games seem more alive in the late stages because of 6-6-6. I find it hard to accept anyone debating that as being worthy of serious treatment

 

[Furn2]

The new rules never addressed the actual problem and were never going to increase scoring.

For every extra goal you get from a centre clearance because of even numbers, you're going to miss out on slingshot goals helped by extras in defense.

Same with the kick out, you might get the odd extra Coast to coast goal but youll get less straight over youre head return goals.

 

[inbetween]

No it's not. It's indictment on the broad stupidity of the whingers around here

No-one ever said increasing scoring was the primary objective of the rule changes. No-one guaranteed that everything would work absolutely

The data apparently suggests that scoring has increased after centre bounces and that the game is opened up for up to 60 seconds afterwards

The data apparently suggests no impact around the kick in changes. But it is too soon surely to confirm whether or not the coaching response has been overly focussed on defending these new rules rather than exploiting them

On that note, it is too early to tell whether dominant coaching strategies have dominated any positive (in terms of scoring) impacts due to the rules.

My take is the games seem to be relatively more open/possession based rather than territory / congestion based which has little to do with any rule changes

But games seem more alive in the late stages because of 6-6-6. I find it hard to accept anyone debating that as being worthy of serious treatment

But no doubt that this rule change was brought in to open up the game with a secondary objective of more scoring.
But was it even needed? There was nothing wrong with the game prior to it, and AFL HQ decided to make knee-jerk changes which I personally believe have negligible impact.
There was maybe two seasons of scrappy congested play when the Bulldogs and the Tigers won the premiership and for some reason, it was thought a change was needed. But I personally found nothing wrong with either of their game styles.
And dont get me wrong, Im not complaining about this specific rule change - just the general AFL policy about rule changes. The sliding rule/ below the knees rule to this day is a mess.

 

[D-N-R]

A 3 game trial was enough to bring these changes in.

90 games in and we need more data to see if it's working.

Sounds like the AFL.

 

[Duskfire]

I just feel like there isnt a large enough sample size yet. Not to mention, there are just less s**t teams this year. Teams rarely get destroyed. I don’t think Gold Coast and Brisbane are playing better because of the rule changes.

 

[iluvparis]

The median team scores are 82 points for 2018 and 77 points for 2019.
The median game totals are 165 points for 2018 and 158 points for 2019.

These would be close to significant falls then right?

 

[coldlunch]

scores and 6-6-6 aside (though I actually quite like lower scores as they tend to stay competitive for longer), I'm enjoying the new kick-in rules and lack of runners clogging space

 

[coldlunch]

does anyone have the stats on the average winning margin this year compared to previous?

 

[iluvparis]

does anyone have the stats on the average winning margin this year compared to previous?

Yes - the OP

 

[bungalow_bill]

It feels like there are whole quarters almost with no goals, and then 4-5 each

Lions V Freo

1/ 5 goals 2/ 0 goals 3/ 5 goals 4/ 0 goals