Saturday, November 5, 2016

Being there or being helpful

OK, so, I was listening to the Arsecast, and the assist / real assist thing is back. An edition or so ago, Andrew Mangan was talking about when a player gets an assist for playing the last pass to the scorer, but the scorer does all the work so the assist didn't really play a fundamental part in the goal. He asked for thoughts on how to distinguish 'real assists'. Apparently he's still waiting. It's the weekend, and if I don't find something to do I have to sweep the flat. So.

Obviously the problem with distinguishing assists / real assists is that it involves a qualitative judgment on the last pass to the scorer. Also obviously, there are quality metrics in statistical analysis as well as quantity metrics, but the one tends to be built off the other, eg goals and shots = quantity, conversion rate = quality. Assigning 'real' status to an assist would seem to be a divergence from that, a subjective approach.

(As a side note, and further to my piece on French football terminology for Unusual Efforts last month, in French an assist is a 'passe decisive'*, which sounds a bit better, but is still in statistical terms, the last pass to the scorer. There's a faux ami aspect to this as assister actually means 'to be present at' rather than 'to help with', so on that basis, Mohamed Elneny could definitely be said to have assisté that Ozil goal...Anyway.) 

So, is there a way to objectively rank assists to distinguish the 'real' ones? Paging the xG community here. I don't have shot location data, and I don't know if the peeps who do have data for the pass before the shot. Given that there are also models for expected assists, I'm assuming so. But this is slightly different - not seeking to 'expect assists', but to evaluate assists based on the xG of the goal that resulted. 

For example, if a goal has a very high xG because it is eg a tap-in from 2 yards out, then we might be reasonably confident that the assist was instrumental in the goal. If a goal has a very low xG because it is eg a speculative lob from just inside the halfway line, then the assister might be as surprised by that as the opposition goalkeeper**. 

Now, if the xG is high because the scorer dribbled round five people having received the ball to get themselves into that close position, that is undoubtedly a factor. So would it be possible to find the xG of the location where the scorer received the ball, not where they took the shot?

For example in this [cough] artist's impression of the Ozil goal, Elneny's pass put Ozil in possession in a location Y that I'm guessing has a fairly low xG rating.  

Ozil then did his glorious thang to score from a much better location X. If we use the xG value of Y, the location where the ball was received, this would seem a good way to evaluate Elneny's contribution. It was a good pass, yes, but not very, well, assisty. Using the Y value would reflect this. 

Also, where both locations are the same, the assister would get 'full credit' based on that value. So, fabulous ball in to the box from a corner, towering header from a centre-back 6 yards out, high value assist. This should also take care of the speculative lob situation as that goal would have a low xG rating so even if the scorer only took one touch, the assist would be valued at that low value to reflect that it was probably more a pass, and the assister really wasn't expecting him to do that. 

*EDIT* (I've been for a walk so been mulling things over) Assigning a simple 'per assist' value is all very well, but to gauge a player's contribution (or team's approach) over a longer period, there would seem to be two options :

  1. (value of xG as at point Y / number of assists) x number of assists = equivalent goals

    (value of xG as at point Y / number of assists) will never be 100%, as xG is never (I understand) 1, but could be used as a weighting factor to estimate impact / contribution.                    
  2. value of xG as at point Y / value of xG as at point X = % helpfulness / assistiness

    Thus, if every assist by a player was a corner on to the head of a centre-back, so all X and Y locations, and therefore values, were the same, the corner-taker would be 100% helpful / assisty in those goals. Yes, this could be problematic if an assist was to a 'better' location than the scorer ended up in, but over a larger dataset it seems likely that this would not be the case. But again, need numbers for this. 


On a vaguely related note, there are no pitch markings on these but here are some chalkboards from the 1950s. You're welcome.

'Key pass' sounds like it should help, and like passe decisive may be used in more subjective ways in commentary etc, but Opta define this as "the final pass or pass-cum-shot leading to the recipient of the ball having an attempt at goal without scoring" (so if it had been a goal, it would have been an assist) and 'chances created' is assists plus key passes so also working on the same basis. They do refer to 'second assists' which is "a pass/cross that is instrumental in creating a goal-scoring opportunity, for example a corner or free-kick to a player who then assists an attempt, a chance-creating through ball or cross into a dangerous position." But then we're back to defining 'instrumental'.

** And in this case the assister might actually be the other goalkeeper. This is one of the weirdnesses of stats that can arise for time to time. Remember when Tim Howard scored that goal? That clearly wasn't a shot. But it was goal, so therefore had to be 'a shot'. Otherwise the stats don't work - if I type 1/0 into my calculator, it gets very cross with me, and googledocs verges on the rude, calling me a #DIV/0!. Similarly here, if it's a goal, the pass to the scorer has to be 'an assist', regardless of intent. This is where a quality metric is needed. 

Wednesday, October 26, 2016

A new football formation : 82-8-50

OK so there's this, reported here :
An online poll of more than 4,000 people across England, Wales and Scotland, conducted by the research company ComRes on behalf of 5 Live, found 82% of football fans said they would not have a problem with an openly gay player at their club.
Eight per cent, though, said they would not watch their team if there was an openly gay player in the side.
The survey also reported 61% of football fans believe gay players should come out to help others do the same, while 71% feel clubs should do more to educate supporters about homophobia.
Of the survey sample, 50% said they had heard homophobic abuse at a match, with 51% saying they have heard sexist abuse and 59% replying that they have heard racist abuse.
So. Let's do some bolding.
  • 82% of football fans said they would not have a problem with an openly gay player at their club.
  • Eight per cent, though, said they would not watch their team if there was an openly gay player in the side.
  • 50% said they had heard homophobic abuse at a match.

Those numbers, taken all together, look a bit weird, don't they? Without the bolding.
Now - it's always possible that some of the 82% think of themselves as cool and groovy people who have many gay friends, or at least think that guy in IT who sorts out their caching issues on a weekly basis might be, y'know, but they don't have a problem with him. So they don't think of it as 'homophobic abuse' when they call a player a fucking faggot for skying one over the bar. Like when Martin Samuel apparently didn't realise he was being a prick when he said Joey Barton should 'come out' because it would help solve world hunger or something. That's part of the problem. Homophobic abuse isn't what you say. It's what they say.
And that's the rest of the problem. Them. It's not your supporters that are the problem, absent those 8% who are presumably still disgruntled that these young guys with double-barrelled names are mostly black, rather than the factory-owner's son coming down to help out the lads of a Saturday. It's that fans will throw whatever abuse they can come up with at opposition players, because that's all part of the game. 
We've often seen fans defending their players no matter what. Racism, diving, racism, violence, and racism, mostly. So if one of their players was gay then he'd also probably be defended to the hilt - as long as he wasn't skying them over the bar. Then...meh. But if it was one of their players - them, them their players - then...banter, innit? 
And the 61% can sit down and keep quiet, frankly, because while they might mean well, nobody owes anybody else 'help' here. And the other numbers give you an inkling why gay players might have a long hard think about 'coming out'. 
I'm putting 'coming out' in 'these things', by the way, because here it seems to mean 'tell the world and do a photo feature in a magazine' whereas a lot of people are openly gay without that. Openly gay doesn't necessarily mean publicly gay. If you're in the public eye, then it will obviously be more difficult to make that distinction, but I really hope that if there are any gay men playing in the Premier League right now, they are comfortable. Their mates know. Their colleagues probably. Their family, hopefully. And everyone's fine with it. It's just we don't know. Because we don't need to. We aren't owed an explanation, a clarification, a 'coming out'. 
Thing is, polling data like this is all very well, but 82% isn't everybody and those 8% and 50% numbers would ring likely ring loud in any player's head. FA Chairman Greg Clarke may be amazed and ashamed that nobody's 'come out' yet, but urging caution until abuse has been stamped out has an air of 'leave this to us, lads, it'll be fine' from an organisation that recently lost a manager after 67 days after a tabloid sting. That's not massively reassuring.
All we can hope is that the situation gets better. That the next poll is better. That the fine work done by many organisations continues to grow. And that if a Premier League footballer 'comes out' it is because he feels confident enough in the support of fans, club, FA, and football more generally to do so. Not because he's been caught on tape saying things in another tabloid sting. 

Thursday, September 29, 2016

Philippa gets another MRI

So, six months after round one, the follow-up. As I managed to scare a few of you with my rambling free-jazz approach to introductory paragraphs last time


and back to the rambling. Again, I am writing this to get it out of my head (the temptation to say 'off my chest' is quite strong here) so the tl;dr version is above, basically. And the story of the first one is here, which deals with the mechanics of the experience in case anyone else out there is claustrophobic and getting ready to have one.

I remembered everything, which is good - previous dossier, the contrast solution, rainbow socks because they cheer me up. We had a slight difficult second album moment as the woman putting the line in couldn't find a vein at the first attempt, which meant switching to the other arm (not ideal, as that's the one that's a mess, but bless her she didn't even blink, and mostly just seemed mortified that she hadn't got in first time and that she might be hurting me). As a result of this she was extremely solicitous in the machine room, when I refused the headphones, and the alternative offer of earplugs, saying "but Madame, it will destroy your ears!". I finally convinced her that it was fine, that it was fine last time, that it was fine, and away we went.

This time my elbows scraped the inside of the tunnel. This wasn't as scary as I would have imagined. When I opened my eyes, I could vaguely (no glasses, natch) see outside the tunnel, or at least that the outside of the tunnel was there. This was also comforting. As was the blanket that they put over my legs because it is damn chilly in one of those things.

I got three songs this time. Being mildly less stressed than last time, I was able to discern more from the noise. Not just chunk-chunk-chunk but definite tone changes and the occasional top-end industrial guitar-type noise. Again it was quite hypnotic, and not having frozen legs this time certainly helped in the drifting-off department.

They seem to have changed their procedure slightly, perhaps connected to last time when I got sent back out into the waiting room to await the verdict, where they promptly forgot about me, and, being British, I just sat there. This time, I was stationed in a chair just outside the techs' office - and the machine room - to speak to the doctor. This meant, as one woman left the machine room and they left the door open before the next woman went in, that I was able to get a look at this thing - with glasses - for the first time. Siemens do a lot of good stuff, don't they? When my washing machine packs up I'm definitely buying one of theirs. It's like something from a sci-fi film. A room that felt small when I walked in must be pretty big in reality. You can also hear the chunk-chunk-chunk from outside in the corridor, without the nuances of what you can hear in the tunnel. I wonder if the techs are occasionally driven mad by the noise and have to take personal time.

Anyway. Doctor - different from last time - says I have a fibro-something, but this is nothing to worry about, that it is both 'benign' and 'stable', ironically the absolute opposite of my mood over the last week or so, so the next check-up in six months will not involve an MRI. Just a mammogram / sonogram. Bleah. Weirdly, the trip to that clinic was more claustrophobic than being slid into a big tunnel, as they left me in a windowless changing cabin for what felt like ages and I had to distract myself from hyperventilating with the available reading material (a guidance poster in a dozen languages) so I now know how to say 'bra' in Vietnamese. But this is clearly a good thing overall so I will just deal with that when it comes.

My utter thanks again to Caroline for coming with me, and showing me a fabulous new shop on the way back into town, and Gareth and Felix for joining us for lunch.

So, again - friends, be it tits or balls, check yourselves. And if something seems weird, get checked out. 

Thursday, March 24, 2016

Philippa gets an MRI

I'm writing this because when I write things they leave my head. And I need this to leave my head. It's quite long. Don't feel you have to stick with it. 

Today, I had an MRI.

I'm claustrophobic, so this was a worry. So much a worry, in fact, that I was focussing completely on the MRI and not even thinking about what the *results* could mean.

Let's wind back a bit.

Early February, I was showering, I thought I felt something weird. Got out of the shower and did a proper check - nothing. A few days later, again, in the shower - felt something weird. This time I was sure.

I booked a check-up for that afternoon. No problem. I love the French healthcare system.

The gyneco was lovely - that bit where they have to ask *those questions* and it's all very awkward? She was awesome - so she checked me out and said... "It's probably nothing but let's get you a mammogram and sonogram to be sure".

I rang for the appointment and it has to be at a particular point in your cycle if you have a cycle so...

Three weeks later, I have the mammogram / sonogram. Again, the mammogram tech was lovely - that perfect mix of human and practical that means you feel in control of you, if nothing else. And then the sonogram tech said... "It's probably nothing but let's get you an IRM to be sure".

This is how stressed I was - I didn't even realise that IRM = MRI. I've solved way harder anagrams than that in the past (RIP Araucaria). But that's what I was booked in for, three weeks later. The receptionist at the mammogram / sonogram clinic urged me to call the second clinic if I had any questions. She stressed - any questions. At the time, I didn't know what questions I could possibly have, as I didn't really know what was happening.

I looked 'IRM' up on Wikipedia not to read the details but to check the translation. But I kept seeing the word 'claustrophobia'. I started to panic. Then I started to plan. My questions. Practicing lying still. Buying a sleep-mask so I wouldn't be tempted to peek. Calling on all that CBT that I'd had, what, fifteen years ago?, to work through positive scenarios.

Shortly after this, a friend of mine on Facebook (extremely pregnant, with a cold) put up a post: "Spent an hour this morning flat on my back, trying not to cough, wedged in an MRI scanner approx the same size as my bump, as a normal* control for a study looking into fetal brain development."

The word 'wedged' terrified me. As did 'hour'. But the fact that she - an NHS doctor - did this voluntarily, made me less shaky. Also the * was "shush now". 

Which made me laugh. 

The only people I told about this were the friend who came with me for mammogram / sonogram, and Team FFW, one of whom responded (in a long chain of messages about various subjects) "Does it help to know you only go half in and then out again? When I had a CT scan I was really disappointed - I'd always assumed you went all the way through and out the other end like a car wash!...Think we said publish for day of match".

Again, that made me laugh. 

Eventually I rang up - and I should have done it earlier - the woman who answered the phone was a star. I got maybe two questions in when she interrupted me - it's OK. You go in feet first. You lie on your stomach, it's like a massage table. (pause) A really noisy massage table. We give you headphones, you pick the channel.

Ooh, I thought. That sounds less scary.

So. Today was the day. I slept OK last night - it was the previous night I had the inevitable anxiety dream (in which I was having my MRI while on a business trip to Canada, so there was snow - I've never been to Canada, I just have assumptions - and I got lost trying to find the right door, so, standard anxiety dream there). My friend met me at the tram stop and we trammed to St Eloi, talking about a kid's birthday party she'd been to.

We found the right door pretty quickly. They were very nice on reception. Filling in the questionnaire, I had to check one translation with my friend. And the conversion rate of stone to kg. Winged it on my height in cm.

When the technician came to take me through, she heard I'd been talking to my friend in English. Asked me, very slowly and carefully, can you understand what I'm saying? Yes, I said. I can understand more than I can say, and if I don't understand, I'll ask. You might have to...I waved my arms around to represent 'explaining things in roundabout ways'. OK, she said, that happens with the French people too. And smiled.

I had the injection for the contrast solution - again, I'd been so worried about the MRI I hadn't thought to check about that, I'd assumed it was localised, but no, in my arm - and was led through. And - and here a bit of serendipity, perhaps - I had to leave my glasses in the prep room. I can't see shit without my glasses. So I never really saw the machine.

In the machine room, it was as I'd been told. Lie face down - and this was when I realised something that I hadn't before; when I rang up, I didn't give my name, I'm not 100% sure I mentioned what part of me was to be scanned, but it didn't matter - because this place specialises in that. Only that. Their table is specifically designed for that.

Like I say, I love the French healthcare system.

This was the one nasty moment. When I put my face into the space in the 'massage table', the table was covered with paper, and this had been hollowed under the face-space. The space was restricting, I couldn't keep my head down. I managed to say 'c'est claustrophobe' and immediately both technicians reached into the space and broke the paper so it wouldn't be restricting. I still couldn't keep my head down, the memory made me panic - the second technician said 'you can put your head to the side'.

I took off the headphones, said I didn't want music, and felt much more comfortable. "It's very loud", said the technician, looking worried. "This is OK," I said, lying down, face sideways.

And it was. I did peek. But like I said, I can't see shit without my glasses so it was just white. And the noise? It's loud, yes. But I spent ten-fifteen years going to ATP, genuinely, I own CDs that sound just like that. The middle-eight was particularly inventive.

So that was it. The drip was taken out and I got dressed and went back to the waiting room, and my friend. And then we waited. An older woman was called out to speak to the doctor and when she came back into the waiting room she just gave the \o/ gesture and her friend hugged her and it was awesome. My friend and I talked about global politics and interior decoration and military deployment and how cool midwives are, and I started to get a bit worried that it was taking so long for them to call me in to speak to the doctor about my results.

Turns out they'd just forgotten I was there.

So, eventually, my post-MRI consultation wasn't a formal meeting in a doctor's office but a quick chat in the dark review room, where the doctor said "rien de suspecte".

I have to go back in six months for another MRI to compare with this one, but the most difficult thing there will be aligning the window for the appointment with my slightly capricious cycle. I'm OK. For now. And won't be as scared next time.

My complete and utter love to my friend Caroline for being with me through this (and the last clinic visit). Not being alone was so important.

So, friends - tits or balls, check yourselves. And if something seems weird, get checked out. 

Here endeth the over-serious.

Saturday, January 2, 2016

Coupe de France Round of 64


The Coupe de France;
Sixty-four teams


Prepare to dream,
To fight 
For honour,


Minnows, giants
On the turf


All looking
To make history.
To win