[RichardHKirkando]

Originally Posted by Vandervaart

Surely strikers are the most valuable players, as the object of the game is to win, and to do that you need to score goals, which are scarse. For instance, I reckon Torres and Villa to be more valuable than Xavi and Iniesta.

In some ways, yes. Great forwards are certainly more scarce than great midfielders - according to my findings, only 22 forwards in the Premier League accounted for 1 or more wins on their own, while 50 defenders and 56 midfielders did the same. I think its very likely that having a top 5 striker can give you a bigger competitive advantage over your opponent than having a top 5 midfielder or defender would. Average strikers are more interchangeable, their results depending more on service from the midfield than their own skill.

Example: Aston Villa is playing Fulham. Their top striker, Gabriel Agbonlahor, is worth 2.5 wins over replacement. Fulham's Andy Johnson is worth just under 1 win over replacement. In the midfield, you have Gareth Barry at 3 wins vs Danny Murphy at 2 wins, which is obviously a smaller difference.

So when you're talking about the extreme high-end, those game-changing strikers can be more valuable. If one of those players is not obtainable though, its best to build from the midfield and defence.

[przeszczepan]

Your work is impressive, Colin.

I’ve gone through the recent 7 pages of your blog and there are certainly lots of imaginative concepts and loads of good work done out there.

What I am missing there is a kind of glossary with definitions of the statistics you are putting to practical use throughout your blog. It took me some time to dig through your earlier posts to find what you mean by all the abbreviations. I am not saying it was unpleasant, though

I particularly liked the 2008/09 Premier League Shot Quality bit. Have you ever looked at how a logistic regression approach values shots on goal depending on the circumstances (distance from goal, angle, proximity of the defender, previous action, …) it has been taken in?

The paper I have linked to in my previous post uses it as a starting point and takes it a step further to estimate the goal scoring potential in each game situation. Knowing that, each action performed on the field can be assessed based on how much of that goal scoring potential is created or lost by performing it. As a result, players’ performance and various types of team moves can be assessed based on how much they contributed to the chance of scoring a goal by their own team and by the opposition.

Some of the desirable characteristics of this methodology include:

- a goal scored by a striker is not exclusively his own contribution if it has been worked out all the way through the midfield; similarly merits for a goal conceded are distributed as a result of the opposite team’s build up not opposed to the sufficient extent by the defending side and not only goalkeeper’s fault for example;

- a great pass opening the striker’s way to the goal remains a great pass if the latter fails to convert it to a goal; if he does fail, the passer is rewarded for the opportunity he had created irrespective of the striker’s action and the striker is punished for the missed chance (even though he is rewarded for finding himself in the good position); the goalkeeper shares the merits (positive or negative) with the striker if the latter had tested him;

- in preventing the opposite side form getting their goals, defending creates results (victories or losses) as much as the offensive actions do;

- a pass into the penalty area allowing strikers to get into a shooting position is much more valuable than a pass in the middle of the field; similarly a key tackle of the last defender which prevents the one-on-one striker vs. keeper situation is worth more than any other.

One of the things I find the most appealing in this approach is that the goal potential created by all the players on the teams sums up to the number of goals scored and conceded by those teams by definition.

The methodology developed in this paper allows for a wide range of practical applications:

1. Comparison of various options of playing the ball available to a player in a given area of the field under given circumstances. Separation of irrational strategies from those that should be chosen between, given the current result of the game and time remaining to the end of it.

2. Identification of strengths and weaknesses of a given team based on the effectiveness of past performance in a given zone of the field and with a given type of action. Particularly effective patterns of play may also be recognized as a series of productive actions.

3. Quantification of players’ input in the result of a game which combines both the amount and the quality of their effort. In the short run this could form the foundation of a team selection process and in the long run may be one of the fundamentals for pricing players.

Szczepański, Łkasz: International Journal of Performance Analysis in Sport, Volume 8, Number 2, July 2008 , pp. 55-66(12)

[happyforever]

There has been a whole thread on this issue before:
http://www.bigsoccer.com/forum/showp...3&postcount=20

I seriously admire people working on it, but fear that if you want to get the best grading for different players, go and ask the Asian bookies. They simply put their wallet where their mouth is!

[Vandervaart]

Off topic and probably already mentioned dozens of times in the beginning of this thread, read Moneyball last weekend. Great book. Too bad that it was published before Epstein's success at the Red Sox.

[ElChupacabra67]

Originally Posted by przeszczepan

Your work is impressive, Colin.

I’ve gone through the recent 7 pages of your blog and there are certainly lots of imaginative concepts and loads of good work done out there.

What I am missing there is a kind of glossary with definitions of the statistics you are putting to practical use throughout your blog. It took me some time to dig through your earlier posts to find what you mean by all the abbreviations. I am not saying it was unpleasant, though

I particularly liked the 2008/09 Premier League Shot Quality bit. Have you ever looked at how a logistic regression approach values shots on goal depending on the circumstances (distance from goal, angle, proximity of the defender, previous action, …) it has been taken in?

The paper I have linked to in my previous post uses it as a starting point and takes it a step further to estimate the goal scoring potential in each game situation. Knowing that, each action performed on the field can be assessed based on how much of that goal scoring potential is created or lost by performing it. As a result, players’ performance and various types of team moves can be assessed based on how much they contributed to the chance of scoring a goal by their own team and by the opposition.

Some of the desirable characteristics of this methodology include:

- a goal scored by a striker is not exclusively his own contribution if it has been worked out all the way through the midfield; similarly merits for a goal conceded are distributed as a result of the opposite team’s build up not opposed to the sufficient extent by the defending side and not only goalkeeper’s fault for example;

- a great pass opening the striker’s way to the goal remains a great pass if the latter fails to convert it to a goal; if he does fail, the passer is rewarded for the opportunity he had created irrespective of the striker’s action and the striker is punished for the missed chance (even though he is rewarded for finding himself in the good position); the goalkeeper shares the merits (positive or negative) with the striker if the latter had tested him;

- in preventing the opposite side form getting their goals, defending creates results (victories or losses) as much as the offensive actions do;

- a pass into the penalty area allowing strikers to get into a shooting position is much more valuable than a pass in the middle of the field; similarly a key tackle of the last defender which prevents the one-on-one striker vs. keeper situation is worth more than any other.

One of the things I find the most appealing in this approach is that the goal potential created by all the players on the teams sums up to the number of goals scored and conceded by those teams by definition.

I've been working on applying Sabermetrics and linear weights in particular as applied to soccer for the last few months. I've come up with one measure of Player Production: http://nordeckeluchador.blogspot.com...rs-player.html

but it needs work. The measures of Team production I'm more happy with but am still doing much needed research. Stumbling on this thread was a godsend.

[brew42]

Hey

I have recently developed a Gaelic Football/Hurling Tracker for the iPhone. Check it out in the iTunes Store @ iTunes.com/apps/gaatracker. Its something we use quite a lot for gathering & viewing stats on Gaa games.

Would people use a similar app for soccer. Check out Footy Tacker @ iTunes.com/apps/footytracker

I think it could be useful for minor teams that don't have premiership budgets

[wolf6656]

Originally Posted by TomEaton

I once ran a study on the MLS possession statistic to determine whether having more possession correlated with winning (the article was in the 2001 American Soccer Analyst). Out of the 170 games I studied, the team with more possession had a record of 75-67-28, slightly better than .500. The interesting thing, though, was that where possession was really lopsided (one team had at least 56% of the possession), the team with more possession was only 18-24-10. I have some theories as to why this might be, but I won't bore you with my opinions. The point is, there is a correlation, but not a particularly strong one. I would have liked to have looked at some numbers for other leagues to see if the results were similar, but I didn't know where to get the numbers. I hope the Matchanalysis people can keep track of stuff like that.

Did your study involve possession in different parts of the pitch? Or perhaps which players had possession for which percentage of the team's totals? Where on the pitch did certain players or certain positions have possession? If your midfilelders have 70% of their possession on your side of half then what good does it do you? If your team has 60% of its possession in your own end it doesn't help you, or does it? You are right, that simple possession is largely meaningless.

The same with merely reporting the number of completed passes. Where were the passes completed? Were they forward? Were they short tic-tac crosses behind midfield, or long accurate crosses to players in the area? I mean, what works for Spain doesn't necessarily work for everyone else, but man does it work for Spain!

The relationship between shots at goal and shots on goal? Is that telling? For individuals, or for teams?

For sabremetrics to be meaningful in soccer, we first have to identify which quanta we should be counting. Soccer is more fluid than baseball or gridiron football, and thus is kind of like trying to nail jello to the wall.

Yet, there are plenty of stats for hockey that seem to work, and hockey is the closest heavy stat sport to soccer in terms of fluidity. But at the same time, a great quality defensive defenseman in hockey is harder to find on a scoresheet. Plus-minus helps, but has to be measured against time spent against the opponents best players vs another defender's time spent against lesser players.

Actually soccer has that advantage in that there are limited substitutions, so every player is pretty much on the field against every other player, There isn't line matching as in hockey.

I think that the very elusiveness of soccer is the greatest part of its appeal. The sport was tailor-made for the Irish. They can argue about it and wax poetic about it at the same time. I learned about soccer from an Irishman, and it was the poetry of his descriptions that sold me. Even when he was angry about "talking points" he was always poetic. He learned to LOVE hockey, while living in northern Manitoba. (You try to find a soccer score up there), but soccer was always number 1.

Soccer isn't a table of stats, as much as Pat used to carry around the soccer newspapers with page after page of scoresheets and tables. Soccer is a never ending story, with plot twists and drama. It was Pat's descriptions of that drama that sold me on the sport. I have yet to find a more meaningful stat than 2:1 (a.e.t.)..........but I will keep searching. hahaha!