Since the 2019/20 season, controversial referee calls in the English Premier League may be technically reviewed and, if deemed necessary, corrected. Using a Twitter analysis of 129 games in the English Premier League, a research team has now determined how decisions made by video referees affect the mood of the fans.

For its 2019/20 season, the English Premier League introduced the video assistant referee (VAR). Dr. Otto Kolbinger and Melanie Knopp from the Chair of Performance Analysis and Sports Informatics at the Technical University of Munich have now investigated the extent to which this influences the mood of audiences.

A total of 643,251 English-language tweets from the social media channel Twitter were included in the study, which investigated 94 VAR incidents from 129 games. Of these, over 58,000 tweets (9.1 percent) were directly related to the video referee.

Analyzing Twitter tweets using artificial intelligence

For their analysis, the team employed «text mining,» an algorithm-based analysis process which unearths structures of meaning buried in text data. The study focused on the automatic extraction of tacit knowledge from large amounts of text data, in this case tweets, collected via an interface.

«We used the official hashtag for each game to ensure that the tweets really refer to the game in question,» explained Dr. Kolbinger, elucidating the procedure. «We also, for the first time ever, used a new text classification algorithm. In our case, it performed better than algorithms used in previous studies.»

To avoid so-called overfitting — the over-adaptation of a model to a given data set — the team allowed only a fraction of the variables to flow into each individual step during model fitting.

Story Source: Materials provided by Technical University of Munich (TUM). Note: Content may be edited for style and length.