Football transfer market

How much money do football clubs pay/receive in the transfer market

Every year, millions and millions are paid to player owners, where rich clubs pay enormous amounts of money and less affluent clubs receive smaller amounts in exchange for players they have schooled.

We found in Kaggle an interesting dataset registering the top 250 transfers in the football world each year from 2000/01 to 2018/19, which we explored to gain some insight:

There are a total of 4700 lines, each one corresponding to one transfer operation

We are interested in operations between clubs, so we decided to study the network of clubs related by transfer operations between them, the weights of the edges being the sum of the fees paid by one team to the other.

We renamed columns (Team_from, Team_to, Transfer_fee) as (Source, Target, Weight) and imported just these three columns to Gephi, after converting the fees to M€, and using the strategy of merging parallel edges by summing their weights:

Edges merging strategy: Sum

We end up with 615 clubs and 3710 edges between them, the “missing” edges being related to repetead operations between the same clubs.

We computed weighted degrees and modulatity classes before trying any layout, just to have a picture of the situation:

Weighted in-degree, the volume of acquisitions

Sorting by weighted in-degree, we can easily find the 20 clubs which spend more money:

20 clubs which spent more money

and sorting by weighted out-degree, we can find the 20 teams which made more sales:

20 clubs which made more sales

It is very easy to find the 20 clubs with most positive balance:

20 teams with most positive balance

and the clubs with most negative balance:

20 clubs with most negative balance

This is not a financial study, but simply a picture of how much money circulates between clubs just for players buying/selling. Ticket sales, TV rights, publicity, sales for fans, etc. and on the other salaries, prizes, commissions, maintenance of installations, and so on, are not considered.

But it shows clearly how different different leagues are.

Fanally, a partial view of the network, where some organization by national leagues may be guessed.

Partial view of the clubs network

Please comment.