Ties in the National Hockey League: An Overtime Bonus

• Activity Number: 447
• Type: Contributed
• Date/Time: Tuesday, August 11, 2015 : 2:00 PM to 3:50 PM
• Sponsor: SSC
• Author(s): Paramjit Gill*
• Companies: The University of British Columbia
• Keywords: Poisson distribution ; Hockey ; Diagonally inflated double Poisson ; Scoring intensity

Abstract

In the point system used in the National Hockey League (NHL) since 2005, not all games are valued equally. If a game is decided during the 60-minute regulation time, the winning team gets two points and the loser gets none. If game is tied at the end of regulation time, the winner is decided by an overtime play or shoot-out. Such a game is worth a total of three points with the winner getting two points and the loser earning one point. It has been suspected that teams might be exploiting the point system to their mutual advantage. We present an analysis of scoring data from the 1998-99 to the 2010-11 NHL seasons to compare the prevalence of tied games. Poisson and modified Poisson probability models are fitted for the team scores at the end of regulation time to model the occurrence of tied scores. In addition, scoring intensities are compared under different situations and over the seasons.