The Effect Of Being Observed

Two of my favourite Twitter accounts had this conversation on Saturday evening.

@thisisanfield does it? Couldn’t it also mean that his injury is more severe than first thought? Hopefully it’s not & he’ll be fit! #InForm
— AnfieldIndex (@AnfieldIndex) September 7, 2013

I had been looking out for an example like this after reading that Bayesian probability means that two people can update their beliefs differently on the same information.

When This Is Anfield is correct is when we can observe the length of an injury. If a player is expected to be out for two weeks but then does not play in two weeks time, it is far more likely that the manager was being cautious than that he is now out for two months.

I have set up a fiddle http://pythonfiddle.com/modelling-injuries-bayesically for the case where Anfield Index is correct - the case where we have not observed the expected length of the injury. I have taken the following injury lengths in weeks [1,2,3,4,6,8,13,26,52] and given them probabilities of 40%^(array index + 1) - except for 52 which gets whatever is left over.

So what do we see?

Away Goals Rule: YOLO!

I saw a tweet on Sunday evening linking to an NPR article titled 'New Teen Buzzword: Yolo'. I had seen the word recently when a young wrapper died moments after tweeting the following:

Drunk af going 120 drifting corners #FuckIt YOLO

Some wise commentator pointed out  that the phrase could equally be 'you only die once'.

This reminded of the Away Goals rule. Often after a team has a 1-0 away victory I have heard someone say that they have a crucial/vital/important away goal. The away goals rule means that in an event of a tie after two legs the team with the most away goals advances. Of course since it is a tie that means they must have scored fewer home goals - maths! Furthermore they have conceded fewer home goals but conceded more away goals.

I propose the Away Goals Conceded rule. I don't see many people pointing out that a team that loses 1-0 away from home has conceded the vital away goal.

Bank-Holiday Rule-Change Monday

This idea comes from Fangraph's "Rule Change Friday", an idea to promote discussion on potential rule changes in baseball. I thought this would be good to apply to football. It seems like there has been a lot of controversy recently. So we have a guest blogger, David Weadick, who is not happy with the 2005 changes to the offside rule. I do like to provide balance so here is an article from the Guardian praising those changes for enabling Barcelona and Spain's recent dominance.

Enjoy!

Geoff Shreeves vs Twitter

When I came home from bridge on Tuesday night Twitter was aflutter over remarks made by Geoff Shreeves to Islanovic during the post-match interview. Here is a video clip mixing it with The Simpsons' episode where Lisa dates Ralph:



Quotes after the jump:

The New Big Five (or Six)

Back in 2003 Liverpool were coming off the mini treble and a second-place finish in the Premier league with a record number of points. Optimism was high and I came up with "The Big Five": Gerard (Houllier) Gerrard Owen Hyypia Vignal

I recently came accross the Online Encyclopedia of Integer Sequences and so I put in the above numbers.

Not recalling Hyypia's number, I entered 10, 17, and 27 as a sequence and immediately realised I had missed a trick. The preceding numbers are the third-to-fifth numbers of a Fibonacci sequence beginning with three and seven. This would have meant having Abel Xavier and Harry Kewell in "The Big Five" but I think the tradeoff is worth it.

Next I loaded up the current squad page to see if there were any Fibonacci sequences lurking in there. This is what I came up with:

• 3 Enrique
• 5 Agger
• 8 Gerrard
• 13 ----------
• 21 Lucas
• 34 Kelly

This looks pretty good to me. Just sign a world-class no. 13 and call it a day.

This Used To Be My Bread And Butter ..

.. but then the walls got their act together.