Chelsea strikers before Lukaku

 

Problem Statement

It is the summer of 2018. The head scout of your club (one of the biggest in the Premier League) wants to scout for a particular position from anywhere in the top 5 leagues using Wyscout data.

 Forward, Chelsea

He is interested in hearing about a variety of methods for scouting players, so he asks you to try out one of the methods from the course or even one of your own. You should primarily use the Wyscout data but can also use Transfermarkt to find the prices of players in summer 2018.

You should do the following steps:

1, Implement one of the methods (plus/minus, percentiles, Markov chain, possession chains, or one of your own) on the data. Decide on a suitable metric for ranking players and make a top-10 list of players in your position for the whole league.  Write a simple non-technical text (half a page) explaining your metric to the scout and what assumptions it makes. Provide a separate runnable piece of code (preferably in Python) which when put in the directory of the Wyscout data creates the top 10. This code must be a single file and only uses standard libraries (mplsoccer is fine)

2, Use your metric to find a single player in another league (not the Premier League), who you would recommend signing. Add additional statistics and visualizations to explain the strengths and weaknesses of that player (these can use World Cup data where appropriate). Create a two-page report, in a poster style, with as many visualizations as you want but max 2 pages on that player.

The metric of choice

I used the G-xG(Goals minus Expected Goals) metric for ranking forwards in the Premier League and to see how our forwards compare to other strikers in the league. xG is a good indicator for a forward’s ability to find the right place to receive a pass so that the striker has a higher chance of scoring a goal. However, xG is not a good indicator of a player’s form or how well does a striker finishes his chances. But if we calculate the xG and subtract it from the goals we would get a metric that does show us the player’s ability to create great shooting opportunities while also scoring these chances. The higher G-xG the better the player is, for example, if a player scores 5 goals out of 6 chances that have a total of 4.5 xG that means that the player has a positive G-xG of 0.5. We can also have a negative G-xG which is the case for two of our 3 forwards. I have removed all shots that are not from open play and headers so I only included shots and goals scored with either foot. Another assumption I made is that the xG model uses the distance from the goal and the angle of the shot to calculate the xG. Last season(2017/2018), Mohamed Salah was at the top of the G-xG list with an outstanding 12.2 G-xG surpassing all the other forwards in the league. Followed by Aubaymeng and Firimino who have 4.9,4.7 respectively. Our forwards, Eden Hazard, Alvaro Morata, Oliver Giroud ranked 5th, 75th, 61st. Morata is the second-worst G-xG in the whole league with -3.2 scoring only 4 goals out of 7.2 xG chances from open play followed by Chrisitan Benteke who followed to score any goals from an xG of 5. Eden Hazard G-xG is 3.9 higher than other forwards like Jamie Vardy (3.2), Raheem Sterling(3.1), and Sadio Mane(2.2) while Giroud had a G-xG of -1.0 which looks bad on paper but considering he did not play as many games as Morata it is a pretty okay score.

The team has already bought in Kepa, Pulisic, and Jorghino for 80,64, and 57 million euros respectively so we do not have a lot of room to work with. With Morata and Giroud underperforming, we need still to find a forward that has a high G-xG. We need to look for a cheap and young forward that we can sign for under 8 million euros. I suggest Youssef En-Nesyri, the 20 years old Moroocoan forward plays for Malaga who just got relegated from La Liga. A club named CD Leganes has offered 6 million euros for the striker, although we can easily hijack the deal. En-Nesyri has a G-xG of 2.0 converting 2 total xG chances into 4 goals. For forwards that are under the age of 27(before they reach their prime), Youssef En-Neysri is ranked 15th, and other strikers are cheaper and have a better G-xG value such as Marco Tumminello and Mariusz Stepinski who both play in the Serie A but neither of them represented their national team. Youssef En-Neyrsi played in the last World Cup and scored a goal for Morocco in the match against Spain that ended 2-2. Youssef En-Nersyi has 15 caps and scored 4 goals for Morocco. Morocco came on as a sub in the second half to score a goal that gave Morocco the lead. That’s why some of his passes and positions on the pitch are in Morocco’s half as they were trying to park the bus to keep the lead but Morocco failed. Most of En-Neyrsi’s movement is on the right. This is great for the team as you need to make sure that our new signing does not take space away from our best striker in the team, Eden Hazard. He can also recover the ball close to the opponent’s penalty area meaning he can help the team in having the ball in dangerous areas.

Shot map of Spain vs Morocco

Positions where Youssef En-Nesyri received the ball in

Ball Recovery map of Youssef En-Nesyri