PLCQ: Twenty Game Round Up
Having recently assessed which Liverpool players have been the most creative this season, it's now time to investigate which teams are doing well on the Premier League Chance Quality (PLCQ) front.
Although the most recent gameweek was the twenty-first of the season, I have decided to limit this review to the first twenty, as every team had played ten home and ten away games at that point, which makes for a fairer comparison.
As always, we begin with a reminder of the six zones that I use to determine quality of chance. For the first time I have made a pitch map, which should hopefully make things a little clearer. The key thing here is that we're looking at the area where the pass was received, rather than where it comes from (as sites such as Squawka tend to highlight).

I'll cover assists in detail at the end of the article, but to give you an indication of the importance of creating opportunities in the centre of the box, here are the chance conversion percentages for each area so far in 2013/14:
The figures really highlight the benefit of creating chances in the centre of the box, and once you are outside the penalty area you're looking at less than a one-in-twenty chance of scoring a goal.
Which teams have created the most chances? Liverpool are second overall, but as the table shows, they could benefit from creating more in the centre of the penalty box:
Whether set plays are factored in or not (as per the final column in the above table), the Reds are below average for the proportion of key passes that are received in the central zone of the goal area.
Still, only Manchester City (with thirty-four more) and Arsenal (with sixteen) have created significantly more CBO chances than the Reds, with Brendan Rodgers' boys in a cluster of five teams who have created between sixty-three and sixty-five.
Liverpool have created more chances in the FT zone than anyone else, with seventy-three, but compiling this data has made me realise that a high figure here is probably down to two things:
Counter attacking football. A swift break can leave the attacker running through having received the ball a long way from goal, and in a position that would be unfavourable if part of a more standard attacking move. The Reds often employ this tactic, and have scored the joint-most goals from counter attacks (three) in the league this season.
Frequent dribbling. Liverpool have completed more dribbles than any other Premier League team this season, with five of their players (Suárez, Sterling, Coutinho, Sturridge and Johnson) being in the league's top twenty for successful dribbles per game. The aforementioned players often receive the ball in the final third of the pitch, and then slalom towards goal before unleashing a shot. The players may ultimately shoot from decent areas, but they often get the ball in a less favourable zone. To my mind, it's no coincidence that Spurs, the league's second most successful dribblers, are second for number of FT chances this season.
A couple of other interesting things that I saw in the figures:
A low OFT figure can indicate patience (in the case of Arsenal) or directness (hello, West Ham).
Cardiff have the highest proportion of chances in the centre of the box, once their impressive set pieces are factored in. Only Manchester City and Stoke have created more CBS opportunities, so with Liverpool's shoddy defensive record from dead ball situations, the Bluebirds will no doubt keenly await the Reds' trip to south Wales in late March.
How about at the back-end of the pitch? The teams are sorted in the below table downwards from least chances allowed at the top of the chart.
Liverpool could probably benefit from conceding fewer chances, but more importantly, at least they don't allow too many CBOs. Only Arsenal have allowed their opponents fewer CBOs than Rodgers' team has, and no team has given up a smaller proportion of opposition chances in the most important area of the pitch than the Reds have.
It should however also be noted though that only three teams (Hull, Cardiff and Fulham) have allowed more set play chances in the centre of their box than Liverpool. This won't come as a surprise to any Kopites reading this, but as the Reds have conceded 27% of their goals against from set pieces (seven out of their total of twenty-six) then an improvement here could have a significant impact upon their defensive record.
Teams that finish fourth only concede a goal a game on average, so with Liverpool running at 1.24 opposition strikes per game, a tightening up from dead ball situations could make all the difference.
In spite of that, Liverpool have only allowed 43.4% of the chances against them inside the box, a proportion that only Sunderland (surprisingly, at 43.0%) and Arsenal (41.1%) have bettered so far in 2013/14. The Reds also deserve a lot credit for only allowing fifty-two opposition chances in the box, when CBS' are excluded; that is the best figure on the division, and Rodgers' team have the lowest proportion of their total against (28.6%) there too.
By combining the two sets of figures together, we can see the 'chance difference' for each team, and by each zone. I have sorted the below table from largest to smallest in the CBO column, as that is the key area of this study.

It's probably no coincidence that the top four in the Premier League occupy the top four places in this table, and it perhaps helps to explain the performance of certain other teams too.
Tottenham Hotspur have the second best chance difference in the division, yet we can see that the bulk of this difference (a whopping 72.6%) has occurred outside of the box, where it is far harder to score.
The figures also show why Manchester United have struggled under David Moyes; it's very difficult to imagine an Alex Ferguson team only creating one open play chance more than their opponents in the centre of the box every three games, but that's what the Red Devils have done on average so far.
They may have fallen away in recent weeks, but the CBO figures possibly also explain why Southampton started the season so well, as they have the fifth best CBO difference in the Premier League.
If we order the above table purely on chance difference, it closely measures the actual league table (on January 1st; remember that the most recent round of league games is excluded).
Eight teams (or 40% of the league, if you prefer) is within one place of their actual league position, and none are more than five places out. Overall, the average difference is just 2.3 places, which shows what a good indicator of league position chance difference is.
This is obvious I suppose, but as this is the first season that I have collated this information, I will certainly monitor it to the end of 2013/14 and beyond to see how closely the tables match up once more data is included.
As promised, I'll finish with a look at the assist tallies by zone for the Premier League, with the teams sorted by their total conversion percentage.

Liverpool can be pleased with their placing on the chart here, and notice how they lead the way on FT assists, with the second best conversion rate in the zone, thanks to their impressive counter attacking and dribbling skills as I mentioned earlier.
One team sticks out like a sore thumb though: Tottenham Hotspur, in eighteenth place. Even an average level of conversion would have seen them score eight more goals, as the below table shows.
I have used the average conversion rate for each zone to create an expected goals figure, so that we can see which teams appear to have over- and under-achieved. It won't be perfect of course, but it provides a decent enough guideline for the time being. Unfortunately for Spurs, they are bottom of the pile.
Who knows, maybe an extra eight goals might have perhaps kept Andre Villas-Boas in a job? From a Liverpool perspective, Brendan Rodgers' employment prospects looks secure, as his team have scored seven goals more than the data suggests that they should have.
My one regret with this project so far is not collating 'assists conceded' information to look at which teams dominate which zones at both ends of the pitch. I may yet do this, but as I'm now 210 games behind, don't hold your breath!
It's important to remember that the figures in this article relate to created chances (where Premier League teams average 9.8 per game) as opposed to all shots (where the average is 13.5), and I have found that the 533 goals in the first two hundred matches this season only had 333 assists to set them up.
As approximately ten percent of goals are penalties or own-goals, neither of which will ever be assisted in the Opta stats (let's ignore fantasy football for the time being) this means that around 150 goals this season have not been created at all, but result from defensive errors, rebounds, good old final third regains, and who knows what else.
Despite that fact, the findings here suggest that chance difference aligns very strongly with league performance, and we can see why Liverpool find themselves at the right end of the Premier League. My fingers are crossed that the same is true on both fronts at the end of the season.
Recent posts you might like:
Second Half Swing, and Fine First Halves - How have Liverpool fared in first and second halves, compared to their Premier League peers?
Liverpool’s Chance Champion – A look at which Reds have created the most chances in 2013/14, and who has found the best areas most frequently.
The Time Is Now – Liverpool have started 2013/14 well, but their next five games (in mid January 2014) are key if the Reds are to finish in the top four. This explains exactly why that is.
How Many League Goals Can Suárez Score in 2013/14? – This features a forecast table, which is updated after every match.
LFC Pass Combination Heatmaps 2013/14 – A look at which players have been most involved pass-wise, and who they’ve linked up with in every league match this season.
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