This part gives an overview of efficiency and effectiveness in football in terms of factors like attack (offense) and possession. It then uses data to find the most efficient and effective teams in the premier league from the 2019/20 season.
The question doesn’t end for whether or not it is possible only to be efficient, only to be effective or being both efficient and effective. There could be a lot of assumptions or opinions for this. Being efficient could mean less quality but also less time consumption while being effective could mean more time consumption but higher quality. So is there a sacrifice somewhere or something missing somewhere that leads to both efficiency and effectiveness? Is it even possible?
First let’s understand these terms briefly in what aspects we are going to use these terms in this analysis. You can skip the part to the data study of finding the most efficient and effective teams if not interested.
Efficient: Performing or functioning in the best possible manner with the least waste of time and effort.
Efficiency in a nutshell is based on two different factors : ‘time’ and ‘results’. So basically, efficiency in football will/should be measured in terms of possession as it will represent the amount of time the ball will be with the team. Possession will represent the ‘time’ and for the ‘results’ we can just use ‘shots’. For getting goals in football, the most basic thing is to hit shots, so we will can shots as the ‘result/product’ as it is the desired thing to be achieved for scoring goals. Without shots, you will not have goals.
Effective: Adequate to accomplish a purpose; producing the intended or expected result.
So , basically for finding the effectiveness of a tactical system we can study how effective the tactical system is
in terms of possession efficiency
For example,
| Team | A | B |
| Avg. Possession in the league | 60 | 80 |
| Shots per game | 6 | 4 |
| Possession per shot | 10 percent | 20 percent |
| Remarks 1 | more efficient | less efficient |
| Shots on target per game | 2 | 4 |
| possession per shot on target | 30 percent | 20 percent |
| Remarks 2 | less effective | more effective |
in terms of offensive efficiency
For example
| Team | A | B |
| Possession | 50 | 50 |
| Shots | 10 | 5 |
| Shots on target | 2 | 2 |
| Efficiency in terms of possession | much efficient | less efficient |
| Effectiveness in terms of possession | same | same |
| Effectiveness in terms of shot conversion(Offense) | Less effective | more effective |
In terms of possession: Team A is more efficient as shown by the relation of 5 percent of possession per shot compared to B’s 10 percent of possession per shot. But in terms of effectiveness in terms of possession, both are the same as they need 25 percent of possession per shot on target.
But the one who are trying to study in this category is the effectiveness in terms of shot conversion (in front of goal). So, in terms of offensive efficiency (shot conversion) :
B is more effective in terms of shot conversion than A as A is hitting only 20 percent of their shots on target while B is hitting 40 percent of their shots on target, hence being more effective in while placing shots on target.
A. Finding the most efficient teams
First let’s try to find the most efficient teams in the premier league from last season. One thing to note is that there is kind of an indirect relation between possession and shots. So, the more the ball (possession) you are going to have, the more the shots you are likely going to attempt. So more the possession, the more likely to attempt more shots. We can take a look at the graph below to understand this trend.
While the trend does show that the more the possession you have, the more the shots you are likely to attempt, this doesn’t mean having more possession is equivalent to having more shots. For example, Arsenal has an average possession of 52.9% but only 10.6 shots per game while teams like Southampton, Brighton have more shots (13 and 12.1 respectively) despite less average possession (49.2 and 51.7 respectively) than Arsenal.
This now leads us to efficiency. From the above example, it’s seen that Southampton and Brighton are more efficient than Arsenal. Arsenal is basically attempting 1 shot for every 4.99 percent of its total possession (52.9%). While Brighton is attempting 1 shot for every 3.78 percent possession being more efficient in terms of possession compared to Arsenal.
The graph below shows the most efficient teams in the PL(2019/20).The y axis has values of shots per possession (reciprocal of possession/shots ) instead just so the y-axis doesn’t need to be reversed and can have increasing values from bottom to top.
The top 5 most efficient teams:
- Man city: 0.308 shots per possession, 3.244% of possession per shot
- Chelsea: 0.279 shots per possession, 3.574% of possession per shot
- Southampton: 0.264 shots per possession, 3.784% of possession per shot
- Aston Villa: 0.260 shots per possession, 3.840% of possession per shot
- Liverpool: 0.259 shots per possession, 3.845% of possession per shot
B. Finding the most effective teams
As discussed earlier in the artcile, we are going to look at effectiveness from 2 views (in terms of possession and in terms of shots)
B.1 In terms of possession
This sub category is just finding out if the team’s tactical system is effective in terms of possession. Being efficient with possession means just being able to hit shots but to find out how effective that system is in terms of possession, we will have to take a look at how much percent of possession the team takes per shot on target.
There is something we need to know first. As with possession and shots, there is also somewhat an indirect relation between possession and shots on target. I mean its common sense to even guess that, isnt it ?. While having higher possession doesn’t mean you will have higher shots on target, the more ball you are gonna have, the more likely you are expected and should be able to create more chances, hence more shots and also more shots on target.
The graph below shows the posssesion and shots on target stats from Pl teams (19/20 season).
As seen by the trend, the higher the value of possession, more likely you are to have higher shots on target. But obviously it’s only the trend and doesn’t really show all things.So, we will take a look at a graph which includes values of shots on target/possession as shown below.
As seen by the trend, the higher the value of possession, more likely you are to have higher shots on target. But obviously it’s only the trend and doesn’t really show all things. So, we will take a look at a graph which includes values of shots on target/possession as shown below.
The graph above shows the most effective teams in terms of possession. The higher the value of shots on target/possession, the more effective the team is when it comes to hitting the shot on target in terms of possession.
The 5 most effective teams in terms of possession:
- Man City: 0.107 shots on target per possession, 9.34% of possession per shot on target
- Liverpool: 0.100 shots on target per possession, 9.93% of possession per shot on target
- Chelsea: 0.098 shots on target per possession, 10.15% of possession per shot on target
- Man United: 0.097 shots on target per possession, 10.30% of possession per shot on target
- Southampton: 0.095 shots on target per possession, 10.46% of possession per shot on target
Now we can combine data values both from shots/possession and shots on target/possession and plot a graph using the values. This wil basically give us an idea of which teams are both efficient and effective (in terms of possession, which teams are only efficient but not effective in terms of possession and so on.
The graph is plotted below with values of shots/possession(efficiency) on the x-axis and shots on target/possession(effectiveness) on the y-axis.
The 2 average values for both the stats is taken as per the data from the premier league teams and can be used to identify the efficient and effective teams just from the four parts the two lines divide the graph into.
Bottom left part of the graph : Neither efficient nor effective with possession as compared to other teams
Botton right part of the graph: Efficient but less effective with possession as compared to other teams.
Top left part of the graph : Less efficient but more effective with possession as compared to other teams.
Top right part of the graph: Both efficient and effective with possession as compared to other teams.
Teams that fall under the top right category : Man City, Liverpool, Chelsea, Southampton, Man United, Everton, Leicester, Aston Villa, Newcastle
Well , we just found out the efficient and effective teams in the premier league in terms of possession from the 2019/20 season but there is something more we need to do.
B.2 In terms of shot conversion
There is a major difference between being effective in terms of attacking (shot conversion) and being effective in terms of possession. Being effective in terms of possession is just finding out how effective the team’s efficiency is and might not reflect the team’s effectiveness in front of goal which can be found in terms of shot conversion.
For example,
| Team | A | B |
| Avg. Possession in the league | 80 | 80 |
| Shots per game | 8 | 2 |
| Shots on target per game | 2 | 2 |
Here is the thing, Team A is more efficient and also more effective in terms of possession as shown by their 10 percent of possession per shot and 40 percent of possession per shot on target compared to 40 percent of possession each for Team B.
But is being effective in terms of possession is really being effective overall?
Team A has only hit 20 percent of their shots on target while Team B has placed 100 percent of their shots on target. So Team B’s tactical system/setup is actually more effective as shown by their effectivness in front of goal.
While a team with a higher value of shots conversion percentage will most probably be having higher shots on target/possession, it always might not be the case as a higher value of shots on target/possession doesn’t mean anything if the team has a higher difference value of (shots/possesion – shots on target/possession) showing they are hitting many shots but most are off target.
Now, back to find the most effective teams in front of goal , we will be looking at the percentage of shots on target and just see which teams have a higher value compared to other teams in the league. The graph can be seen below.
The most effective teams in the league: (in terms of shot conversion%)
- Liverpool : 38.71 shots on target per 100 shots
- West Ham : 38.54 shots on target per 100 shots
- Manchester United : 38.13 shots on target per 100 shots
- Arsenal : 36.79 shots on target per 100 shots
- Southampton : 36.15 shots on target per 100 shots
Now, we will take a look at two different metrics and use graph to find the efficient and effective teams in terms of overall quality in the premier league. As discussed earlier, the values for effectiveness are taken in terms of shot on target % and for efficiency; the only reasonable thing is to look at the values calculated in terms of possession i.e use shots/possession.
So using x-axis for values of shots/possession(efficiency) and y-axis for shots on target%(effectiveness), the following graph is produced.
Now, using the average values in the league for both metrics (shots per possession and shots per target %), we have drawn 2 average constant lines from x=0.243 (avg. value for shots per possession in the league) and y=33.72 (avg. value for shots on target percentage). Now from the graph above we can bring conclusions for a team’s efficiency and effectiveness.
Bottom left category:
These are the worst teams in terms of efficiency and effectiveness in the league as per the data. The teams falling under this category are neither efficient with the ball nor effective.
Bottom right category:
These are the above average teams and good teams in terms of being efficient. While they are efficient with the ball, the chances and the positions they have created those chances from are not good enough and are of low quality resulting in less effectiveness. It also means that the teams could be playing fast and direct resulting in efficiency but loss of quality (effectiveness).
Top left category:
These teams are not efficient with the ball but are effective. When you are not being efficient you expect the team to create better chances and hit shots from better angles, positions and take the best shots. All the teams that are under this category are teams that take time on the ball but create better chances/shots.
Top right category:
This is undeniably the best category and just says everything about the tactical system. Being both efficient and effective with the tactical system is really impressive. Being efficient means you are trying to play ball fast, create more chances/shots than less efficient teams which can result in loss of quality at the end product making it less effective. But these teams are efficient and also effective at the same time. It just speaks how good of a tactical system they have.
The best premier league teams in terms of efficiency and effectiveness (in no rank):
- Manchester city: 3.24% of possession per shot, 34.71 shots on target per 100 shots
- Liverpool: 3.84% of possession per shot, 38.70 shots on target per 100 shots
- Chelsea: 3.57% of possession per shot,35.18 shots on target per 100 shots
- Manchester United: 3.92% of possession per shot,38.12 shots on target per 100 shots
- Southampton: 3.78% of possession per shot,36.15 shots on target per 100 shots
- Everton: 3.98% of possession per shot,34.95 shots on target per 100 shots
- Leicester: 3.93% of possession per shot,34.28 shots on target per 100 shots
Well that was all about the data analysis for finding the best premier league teams in terms of efficiency and effectiveness. But is there some factor that is the key to become both efficient and effective? What really is the advantage of being both efficient and effective? All these things will be further studied in the second part of the article.