Abstract
This is the first study in this sphere, where we focused on the number and distance of errors of line umpires in the important international tennis matches played in Czech Republic. Hawk-Eye had been used on the court, which allowed reviewing the umpire's call.
Hawk-Eye is being used at all ATP, WTA tournaments and Davis Cup and Fed Cup matches. It helps to make accurate call, when a player challenges the call.
Our aim is to find, how successfully are able to make the line umpires their calls and what is the average error distance. We had data from the official Hawk-Eye scorecard.
Results showed umpires were wrong in 27,7 % of their challenged calls. The average error was 20,8 mm.
Czech line umpire officiating is on equal level as grand slams line umpires. More experienced line umpires should be placed on far side line, because the chair umpire can hardly correct a wrong call there.