transfers

Data on European football clubs' player transfers, as found on Transfermarkt, since the 1992/93 season.

IMPORTANT: As of July 2022, transfer fees are now in EUR (taken from the .com Transfermarkt site), not GBP (taken from the .co.uk Transfermarkt site) due to a distortion of older fees being converted with a recent exchange rate.

Contents

Data

Transfers can be found in the data/ directory, in .csv format. There's a file for each of these leagues:

• English Premier League (premier-league.csv)
• English Championship (championship.csv)
• French Ligue 1 (ligue-1.csv)
• German 1.Bundesliga (1-bundesliga.csv)
• Italian Serie A (serie-a.csv)
• Spanish La Liga (primera-division.csv)
• Portugese Liga NOS (liga-nos.csv)
• Dutch Eredivisie (eredivisie.csv)
• Russian Premier Liga (premier-liga.csv)

Common variables:

Header	Description	Data Type
club_name	name of club	text
player_name	name of player	text
position	position of player	text
club_involved_name	name of secondary club involved in transfer	text
fee	raw transfer fee information	text
transfer_movement	transfer into club or out of club?	text
transfer_period	transfer window (summer or winter)	text
fee_cleaned	numeric transformation of fee, in EUR millions	numeric
league_name	name of league club_name belongs to	text
year	year of transfer	text
season	season of transfer (interpolated from year)	text
country	country of league	text

Config

• config/league-meta.csv - leagues to scrape

New leagues can be exported by adding rows to the config/league-meta.csv file. Required columns are league_name, league_id and country. To get league_name and league_id, extract these from the transfermarkt URL for any leagues' transfer history:

www.transfermarkt.com/{LEAGUE_NAME}/transfers/wettbewerb/{LEAGUE_ID}/

When scraping new leagues, it is recommended to remove all the leagues that data has already been downloaded from (i.e. only include new leagues). This cuts on processing time and stress on servers.

Code

R:

• src/scrape-summer.R: retrieves latest summer window's data and appends new observations to CSVs in data/
• scr/scrape-winter.R: retrieves latest winter window's data and appends new observations to CSVs in data/
• src/scrape-history.R: retrieves transfer history by league and exports to CSVs in data/
• src/functions.R: local R functions used elsewhere

Source

All squad data was scraped from Transfermarkt, in accordance with their terms of use.