In an attempt to discover whether refs favor the home team, researchers showed one group of refs videotapes of tackles in the English Premier League with the sound off while another group of refs viewed the tackles with the sound on. The group that watched with the sound off called 15.5 percent fewer fouls against the home team than those listening to the crowd noise. Professor Thomas J. Dohmen says, “referees’ objective judgment capabilities are impaired by the emotional atmosphere in the stadium.”