One for Sure or Maybe Three

Abstract

In order to avoid too many tied games after playing the five-minute overtime period, the National Hockey League (NHL) introduced two rule changes in the 1999-2000 season. First, a team that loses in overtime receives one point instead of zero points. Second, the number of skaters in overtime is reduced from five to four. The theoretical literature analyzing these rule changes predicted that they would also produce the unintended side-effect that more games would reach overtime and recommended that a team that wins in regulation should receive three points (instead of two) in order to counterbalance the converse effect. We are the first to empirically support this theoretical prediction using NHL data and data from Swiss ice hockey, in which the rule changes of the NHL were copied in the 2006-2007 season and in which the three-point rule was also introduced. SummaryIn order to avoid too many tied games after playing the five-minute overtime period, the National Hockey League (NHL) introduced two rule changes in the 1999-2000 season. First, a team that loses in overtime receives one point instead of zero points. Second, the number of skaters in overtime is reduced from five to four. The theoretical literature analyzing these rule changes predicted that they would also produce the unintended side-effect that more games would reach overtime and recommended that a team that wins in regulation should receive three points (instead of two) in order to counterbalance the converse effect. We are the first to empirically support this theoretical prediction using NHL data and data from Swiss ice hockey, in which the rule changes of the NHL were copied in the 2006-2007 season and in which the three-point rule was also introduced.

Inefficiencies in the National Hockey League Points System and the Teams That Take Advantage

“…A related control variable we also considered was whether or not the game was a divisional one. However, this game trait was previously found to be a nonsignificant predictor for the likelihood of overtime in PS3 (Franck & Theiler, 2012), and we feel that conference status may be the stronger predictor as far as team strategy. Specifically, while winning a division guarantees a top three playoff seed within a conference, the remaining five playoff teams can come from any division within that conference.…”

“…The reward for overtime or shootout victories, meanwhile, was kept at two points. Franck and Theiler (2012) found that overtime likelihood in the Swiss NL did not change after the 2006 rule change. Perhaps the NHL, as it considers a…”

“…Specifically, coefficient estimates using models fit without teamdiff were within one hundredth of a decimal point of the ones provided in Table 4. As in Franck and Theiler (2012), we attempted to account for the correlation of outcomes within a team's season using a generalized linear mixed effects model of overtime, including a random intercept for each team and season combination, in addition to the fixed effects in Table 4. These random effects were nonsignificant and did not noticeably change the fixed effect estimates provided here.…”

“…Similar to Abrevaya (2004) and Franck and Theiler (2012), we use the absolute value of the difference in the seasonal average goal differentials between the two participating teams to account for differences in team strength, where a team's seasonal average goal differential is defined as: Seasonal avg: goal differential ¼ Total goals scored À total goals allowed 82…”

Lockouts and Player Productivity

“…However, not only would it be difficult to ascertain information about which players chose to play abroad during this period, such an analysis could be compromised by the myriad changes to league policies made before the start of the 2005-2006 season, including the implementation of the shootout, which were designed to increase game scoring and excitement. Franck and Theiler (2012) and Lopez (2015), for example, identified changes in game outcomes when comparing behavior before and after the 2004 lockout. In this respect, the analysis of the 2012 lockout would be preferred; when NHL play resumed in January 2013, it did so with, by and large, an identical set of rules and incentives to the previous season.…”