INTRODUCTION

Home advantage is a commonly observed phenomenon. It refers to a tendency for teams to win more contests played at their home venue compared to when they play away, and it is pervasive across many sports. For example, during the 2019 regular season the average rate of home wins was 52.9 per cent in Major League Baseball and 60.65 per cent in the National Basketball Association. In contrast, the average home win percentage for English Premier League clubs during the 2018/19 season was 47.63 per cent. However, given the higher prevalence of draws in football, average home losses equate to just 33.68 per cent, leaving the corresponding home “non-loss” percentage of 66.32 per cent. In rugby, which is the focus of the investigation in this chapter, home advantage has been found to be consistently above 60 per cent across both domestic and international-based tournaments.

Understanding the source of this home advantage in various sports has been considered in several studies (for a general overview, see Nevill & Holder ). Among the most important factors identified is the role of the match official (also known as the referee, umpire, etc.) and how their decision-making is influenced by social pressure exerted by a partisan (home) crowd (Dohmen & Sauermann ). However, studies have also looked at increasing the number of on-field officials and, more recently, the use of off-field (third-party) video assistance in relation to critical decisions (Dawson, Massey & Downward 2019).

This chapter investigates how the behaviour of the on-field referee is influenced by third-party assistance, providing some original insights associated with the Pro14 rugby competition. It begins with a review of the related literature and then outlines the Pro14 rugby competition. The remaining sections outline the data and method used in the analysis and discuss the results. The conclusions of the chapter are that the presence of third-party assistance generally increases sanctions on players during matches, but variations exist across on-field officials of different nationalities. There are also potential biases when the on-field official shares the same nationality as the home team, but this is reduced in the presence of the assistance of a third party.