DC Postmatch

MOTM

  • Villa

    Votes: 36 58.1%
  • Maxi

    Votes: 10 16.1%
  • Wallace

    Votes: 18 29.0%
  • Backline/SJ

    Votes: 7 11.3%
  • Harrison

    Votes: 1 1.6%
  • Ring

    Votes: 9 14.5%

  • Total voters
    62
  • Poll closed .
Are you a salesperson for the company? Because that sounded like a marketing pitch. :)

I don't doubt there are analytic models out there, but they all cannot account for the x-factor variable(s) of the individual players (what's their fitness, are they distracted by the fans/weather, did they have a good constitutional that morning, are they having WaG issues,etc) during the free-form run of play.

I'm not trying to rag on you, but advanced stats for soccer are rather silly and self serving.
Worse, my field is data analytics and statistical modelling—I'm a member of the group which is comprised of some of the biggest blowhards and liars to ever grace humanity. ;)

The variables you list are definitely legitimate (and always potentially problematic for results) but should never be a reason to avoid or discount statistical models as helpful tools (otherwise you'd have to throw out nearly all measures/metrics as problematic). All "good" models are merely the "least inaccurate" set of explanatory or predictive equations interpreting the "least bias" data available at this time. They are all wripe for destruction and reconstitution at any time as new, more accurate information and translations are discovered/created.

I rarely think tools are silly—I very regularly think the craftsman is, though, such as the armchair twit you mentioned in your original response. I also think the xG models are limited in very real ways (as highlighted in my original and subsequent posts) and hope they are improved.
 
I actually read the description of xG as rather critical, from someone who thought it had some limited utility but wanted to highlight the limitations.
All the soccer stats nerds I listen to regularly are pretty upfront about the fact that there are a whole host of things which xG doesn't model, but as Sebastian mentioned it's kind of a "least bad for now" way of describing the attacking portion of the game statistically.
 
Worse, my field is data analytics and statistical modelling—I'm a member of the group which is comprised of some of the biggest blowhards and liars to ever grace humanity. ;)

The variables you list are definitely legitimate (and always potentially problematic for results) but should never be a reason to avoid or discount statistical models as helpful tools (otherwise you'd have to throw out nearly all measures/metrics as problematic). All "good" models are merely the "least inaccurate" set of explanatory or predictive equations interpreting the "least bias" data available at this time. They are all wripe for destruction and reconstitution at any time as new, more accurate information and translations are discovered/created.

I rarely think tools are silly—I very regularly think the craftsman is, though, such as the armchair twit you mentioned in your original response. I also think the xG models are limited in very real ways (as highlighted in my original and subsequent posts) and hope they are improved.

I used to work in baseball metrics, and I really wish I had this as a copypasta back then.
 
I used to work in baseball metrics, and I really wish I had this as a copypasta back then.
Haha, I've definitely toyed with the idea of having a general version of this response recorded on my phone for easy play back in quiet meetings with skeptical clients and printed/laminated in large block typeface for rowdy pub debates. ;)
 
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Expected Goals is based on individual shot position relative to goal in conjunction with Opta's model based on "successful shots" which is built from apparently hundreds of thousands of recorded shot positions. It's a probabilistic model already based on a huge universe which is supposedly updated with statistics from all of the top leagues each year. You do not need many matches in a season to be played for it to be valid (although some would argue how accurate it is given some recent widespread changes in tactics, playing equipment like balls and boots, and improvements in overall player skill levels). It is only meant to be a means for benchmarking/assessment and is used by most every team with the resources to get past their paywall these days (including all of CFG's clubs). It's not meant to be a true predictor—there are other metrics for that.

I generally use it as "the best available right now" baseline for how we performed, along with a few other KPMs I think help build a picture of the quality of our play.
Is the xG model you describe above based on Opta the same as the ASA one? eg http://www.americansocceranalysis.com/home/2017/3/6/validating-the-asa-xgoals-model

Or is it like WAR (Wins Above Replacement) in baseball, where there is FanGraphs WAR and Baseball Reference WAR, and while they purport to do the same thing they can vary quite considerably?
 
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Is the xG model you describe above based on Opta the same as the ASA one? eg http://www.americansocceranalysis.com/home/2017/3/6/validating-the-asa-xgoals-model

Or is it like WAR (Wins Above Replacement) in baseball, where there is FanGraphs WAR and Baseball Reference WAR, and while they purport to do the same thing they can vary quite considerably?
Unfortunately, I can't really confirm (with any real confidence, anyway) how similar the ASA and Opta models are; I actually hadn't seen the ASA one (thanks for sharing, definitely going to give it a good look sometime this week—it's great that they include the R code) and Opta keeps the actual technical framework for their model tucked away. That said, they have released some decent blog write-ups about their methodology over the years that you may be interested in (I've included links to a few below). I may eventually put together a comprehensive list of the various interesting models (both commercial and open source) out there in the football analysis world right now, if anyone aside from you, S sbrylski, and I would be interested in that.

http://www.optasportspro.com/about/...e-of-premier-league-goalscorers/mbuBlogsyPost

http://www.optasportspro.com/about/...7/blog-expected-goals-explained/mbuBlogsyPost
 
I only drank 3 beers yesterday over the course of 2.5 hours, and I didn't really feel cold during the match due to utilization of appropriate clothing. Nevertheless, I feel like ass today.

I can't do anything. I still haven't made it in to work. Generalized gross feeling should be a real medical thing.
That Mississippi blood cant handle the cold. Or you just didn't drink enough. I only drank 9 beers over the 3.5 hrs we were in the bronx and i have felt great all week after that win.
 
1. Myth: You’ll get sick if you go out in the cold with wet hair or without a coat

Reality: Being cold (or cold and wet) has nothing to do with contracting the cold or flu virus. The reason we often associate the two is that the flu virus more commonly circulates during the fall and winter than during other times of year, Dr. Jon Abramson told ABC News. So more people are sick relative to warmer months, but the cold weather has nothing to do with it.

http://www.huffingtonpost.com/2014/10/24/cold-and-flu-myths_n_5983736.html
What is the opposite of mythbusting? Myth restoring!

http://www.pbs.org/wgbh/nova/next/body/scientists-finally-prove-cold-weather-makes-sick/
 
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What I like about these videos are the small things that you notice:

- Inside the locker room, the players name cards have their home country on them.
- On the floor outside each locker room stall, there is a blue mat similar to the warning titles in front of the subway (which are typically yellow).
- The entire team celebrates the goal from the defense all the way up, every time
- David Villa calls out individuals players to come over to the supporters for the end of the match to toss the balls.

 
I love how Chanot joins the team to celebrate and then immediately looks around like DC is going to kick the ball off and score while he is out of position unless he keeps an eye on them.
 
I love how Chanot joins the team to celebrate and then immediately looks around like DC is going to kick the ball off and score while he is out of position unless he keeps an eye on them.
Lol, he was always the last one there and kept turning to keep an eye out.

Two other funny moments:

1) before the players walk out (around the 4' mark I think) one of the kids was rough housing with the kid behind her, and then sees the camera and see she's "caught".

2) after Maxi's goal and the initial celebration, Ring hugs Maxi but he bends down a considerable amount
 
Worse, my field is data analytics and statistical modelling—I'm a member of the group which is comprised of some of the biggest blowhards and liars to ever grace humanity. ;)

The variables you list are definitely legitimate (and always potentially problematic for results) but should never be a reason to avoid or discount statistical models as helpful tools (otherwise you'd have to throw out nearly all measures/metrics as problematic). All "good" models are merely the "least inaccurate" set of explanatory or predictive equations interpreting the "least bias" data available at this time. They are all wripe for destruction and reconstitution at any time as new, more accurate information and translations are discovered/created.

I rarely think tools are silly—I very regularly think the craftsman is, though, such as the armchair twit you mentioned in your original response. I also think the xG models are limited in very real ways (as highlighted in my original and subsequent posts) and hope they are improved.

Reading the experts at MLSsoccer.com downplay NYCFC success last season and last game based on the expected goal model is aggravating. It is silly to disregard the model, but the model should not be used as a metric for NYCFC success because we do not have an average striker or a below average striker, we have David Villa, who is a top notch striker.

If, during the 2017 season, Sean Okoli and David Villa each take 100 shots from identical spots on the field, Villa will score more goals. If we increase the number of shots we look at to make the sample more statistically significant Villa will still score more goals. What is missing in the xG models is a soccer equivalent of baseball's WAR, call it GAR -- goals against replacement. Because the xG model considers only where shots are taken on the field and not the quality of the shooter, the model has a serious flaw.

When somebody looks at the xG analysis and sees that the actual NYCFC goals scored is consistently higher than xG the conclusion "NYCFC players are really good" is just as valid (I think more valid) than the conclusion "NYCFC got lucky".
 
Reading the experts at MLSsoccer.com downplay NYCFC success last season and last game based on the expected goal model is aggravating. It is silly to disregard the model, but the model should not be used as a metric for NYCFC success because we do not have an average striker or a below average striker, we have David Villa, who is a top notch striker.

If, during the 2017 season, Sean Okoli and David Villa each take 100 shots from identical spots on the field, Villa will score more goals. If we increase the number of shots we look at to make the sample more statistically significant Villa will still score more goals. What is missing in the xG models is a soccer equivalent of baseball's WAR, call it GAR -- goals against replacement. Because the xG model considers only where shots are taken on the field and not the quality of the shooter, the model has a serious flaw.

When somebody looks at the xG analysis and sees that the actual NYCFC goals scored is consistently higher than xG the conclusion "NYCFC players are really good" is just as valid (I think more valid) than the conclusion "NYCFC got lucky".
I understand what you are saying and agree that anyone that consistently thinks NYCFC are just lucky aren't really looking at the metrics or the performances. But there are additive functions for these models that are often used by individual clubs/firms to further assess performance. WAR (and other player-centric qualitative systems) definitely have their place but the much more dynamic nature of football, as opposed to baseball, makes accurate value-assessment a bit more difficult. However, as I said earlier, I don't use (nor do I advocate using) the xG model in isolation. It is a benchmark that can and should be used with other methods such as short-term trend analysis and individual contribution theory to assess performance.

By the way, even if the model is modified (and hopefully improved) in light of better data or interpretative equations you are always going to have teams that consistently overperform and underperform, that is the nature of benchmarking (if all teams are underperforming or overperforming you have a "bad" model—if every team is within statistically significant parody then you need to start patenting that **** as, with luck and hard work, you're about to all but destroy football and make a lot of money doing it).
 
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I like xG. But I don't think it's a good indicator for how well we played this time around.
Reading the experts at MLSsoccer.com downplay NYCFC success last season and last game based on the expected goal model is aggravating. It is silly to disregard the model, but the model should not be used as a metric for NYCFC success because we do not have an average striker or a below average striker, we have David Villa, who is a top notch striker.

If, during the 2017 season, Sean Okoli and David Villa each take 100 shots from identical spots on the field, Villa will score more goals. If we increase the number of shots we look at to make the sample more statistically significant Villa will still score more goals. What is missing in the xG models is a soccer equivalent of baseball's WAR, call it GAR -- goals against replacement. Because the xG model considers only where shots are taken on the field and not the quality of the shooter, the model has a serious flaw.

When somebody looks at the xG analysis and sees that the actual NYCFC goals scored is consistently higher than xG the conclusion "NYCFC players are really good" is just as valid (I think more valid) than the conclusion "NYCFC got lucky".
But I don't think Villa outperforms his xG consistently, does he?

From the analysis I've read previously, there's very little difference in strikers' conversion rates over the long-term. There's a good article somewhere out in the world that discusses whether "clinical finishing" is a real thing. I think the conclusion was something along the lines of "if it is real, it's even rarer than we make it out to be".
 
I like xG. But I don't think it's a good indicator for how well we played this time around.

But I don't think Villa outperforms his xG consistently, does he?

From the analysis I've read previously, there's very little difference in strikers' conversion rates over the long-term. There's a good article somewhere out in the world that discusses whether "clinical finishing" is a real thing. I think the conclusion was something along the lines of "if it is real, it's even rarer than we make it out to be".
That's what I've read as well. I further remember reading that the main skill of most top scorers is repeatedly getting into a position with the ball where scoring is likely. To a degree, that is what xGoals is meant to measure. But it doesn't, as I understand it, measure the defensive factor. If someone like Villa consistently outpaces his xGoals I think it could be because he not only gets multiple scoring chances as measured by xGoals, but also gets them with comparatively fewer defenders in a positon to alter, limit or block his options.
 
I like xG. But I don't think it's a good indicator for how well we played this time around.

But I don't think Villa outperforms his xG consistently, does he?

From the analysis I've read previously, there's very little difference in strikers' conversion rates over the long-term. There's a good article somewhere out in the world that discusses whether "clinical finishing" is a real thing. I think the conclusion was something along the lines of "if it is real, it's even rarer than we make it out to be".

This is more interesting than what I am working on.

Back of the envelope -- NYCFC had the biggest difference between xG and actual goals in 2016. Villa took 166 out of 463 of our shots (36%) and led the league in scoring. I would bet Villa outperforms xG consistently. TommyMac's long range bombs probably skewed the results more than Lampard's random body parts right in front of goal did.

I once saw a scatterplot of all of Messi's goals and it was dramatic. Huge huge percentage were from the sweet spots right in front of goal between the 6 and 18. The chart became one of my coaching staples.
 
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