What is referee bias‪?‬ Ref bias

I hope everyone enjoys the podcast because I worked hard on it.

Articles from research:

https://www.researchgate.net/publication/273835772_Referee_Bias

https://news.wosu.org/news-partners/2016-11-03/study-nfl-referees-influenced-by-coaches-and-players-sideline-yelling

https://researchportal.bath.ac.uk/en/publications/are-football-referees-really-biased-and-inconsistent-evidence-on-

https://bleacherreport.com/articles/2739652-nfl-referees-association-calls-reports-of-biased-officiating-irresponsible