Analysis on match factor change according to introducing VAR system in K League

Abstract

Purpose The purpose of this study is to analyze the changes in the game factors since the introduction of the VAR system and discuss the meaning of the changes in the K-League.Methods The game factors related to referee decisions (goal, penalty kick, offside, foul, yellow card, red card, additional time) were divided into home and away team and analyzed by two-way ANOVA for 556 games before and 583 games after the VAR system was implemented. All game factors that occurred during the match and additional time were analyzed as independent t-test before and after the implementation of the VAR system.Results First, there was no statistically significant difference between a goal and a penalty kick. Second, the offside was significantly reduced throughout the home team, away team and the entire game(p<.001). Third, fouls were significantly reduced in home teams, away teams and the entire game (p<.01). Fourth, yellow cards were significantly reduced in both home and away teams and the entire game(p<.001). The red card increased significantly throughout the home team, away team, and the entire game(p<.001). Sixth, the additional time showed no difference the first half and the entire game, and was a little reduced in the second half (p<.05).Conclusions As a result of this study, players should not anticipate offside decision and stop playing in critical situations that may lead to a score or penalty kick, and continue playing until the referee makes a final decision. In addition, all red card situations are review through the VAR system, so excessive foul play or unnecessary behavior should be avoided. K-League referees are required to make a more accurate decision in the red card situation, and the time wasted by the VAR system during the game is not much.