Samenvatting

Most aesthetic sports where judges subjectively rate performances can suffer from issues like systematic errors due to biases. Equestrian dressage is defined through the intricate interaction between horse and rider. Assessing these interactions can be particularly complex, often exceeding human processing capabilities. The study focuses on whether the current dressage system predisposes international judges to using biases, and inadvertently favours certain horse-rider combinations. The study examined 510 judging scores, gathered from seven elite-level dressage competitions held between May 2022 and April 2023. The effect of different factors, such as whether riders competed in their home country, if they had the same nationality as the judges, their starting order during the competition, and how they were ranked according to previous performances were analysed. Results showed that all these factors influence the final dressage results. In order to assist judges in providing objective, transparent scores, a clear evidence-based set of judging guidelines should be developed, which would prevent judges from having to resort to cognitive short cuts. That way, the complexity of judging is reduced, making scores more objective, transparent and fair.