Game Theory: Match throwing in badminton
Link:
In the 2012 Summer Olympics, there was an interesting phenomenon in which the badminton players decided to purposely play poor shots into the net in certain games in order to lose the game. For that year specifically, Badminton used the model from other Olympics sports and divided the matches into rounds: first, all players are separated into four groups of four, and the top two from each group play the elimination rounds against the other groups. During one of the group matches, the Chinese double Yu Yang and Wang Xiaoli were facing South Korea’s Jung Kyung Eun and Kim Ha Na. Whichever pair wins the game has to face another Chinese double group who was top in women’s doubles, while the pair loses will face a much weaker opponent. In that case, both the Chinese double and the Korean double groups decided to throw their match so they can at least win a medal. Their act of “play to lose” was definitely not acceptable and disrespectful, both to themselves and to other players. Eventually, both groups got caught and were disqualified due to their match-throwing strategy.
The players’ incentive to lose proposes a valid argument in game theory. Both team 1 and team 2’s dominant strategy is to lose the game so they can face off a weaker opponent and get a medal. Likewise, neither team wants to win the game because they will most likely to lose their chance of getting a medal. The team that loses the first game will have a higher payoff because they will likely to win the second one and advance further. The team that wins the first game, however, is worse off because they will lose the next game and end their Olympic journey from there. As a result, both players are stuck in a Nash equilibrium(lose, lose) that doesn’t exist in reality because one of them has to win.
According to the article, the rules weren’t the main problem that the players start to throw games. The coaches, in fact, believed that the payoff of losing was greater than the payoff of violating the code of conduct; they pushed their players to play against their own will to benefit their country. However, it turned out that no one remembered the winner, but everyone remembered the teams who violated the rules. In other words, the coaches might have had a slightly off calculation when they decided on the payoffs of each decision.