Welcome to Sunday Notes, where we try to rehash important developments occurring on Hockey Graphs and elsewhere in the CORSI twitter league in less than 500 words. I’m sorry if we forgot about your post, or misconstrued what you said. We don’t care. Don’t @ us. Just do better next time. – asmean (w/ a secondary assist from Sean)
Expected goals predict future scoring
An important development has been made in predicting future scoring at the team and player levels. A new expected goals model was unveiled recently, which took into account shot quality. The results were very positive, as the model outperformed score-adjusted Corsi and goals %. It also proved to be descriptive, making it a useful metric in evaluating both past and current performance. The authors hinted at future refinements of this model, which will include splitting forwards and defensemen and looking at special teams specifically. Until then, check out the expected goals maps that will be posted the morning after each game on @dtmaboutheart’s twitter page.
Read for yourself here.
Score states and the neutral zone
We’ve known about score effects for a while now, but not a lot of work has been done to elucidate how they dictate play exactly. Garik16 looked at how score states affect play specifically in the neutral zone from a statistical perspective. Surprisingly, it appears that teams who are leading carry in the puck on a greater percentage of entries. Since carry-ons are regarded as more dangerous, this result challenges the assumption that leading teams are more risk-averse. On the other hand, trailing teams attempted more dump-ins, which led to a greater percentage of failed entries. More research on how score states affect play is underway, particularly zone entries and exits.
Read on for more here.
Why teams should use 4 forwards on the powerplay
In his latest, Matt Cane makes an argument for the use of 4 forwards on the powerplay instead of the standard 3 forward/2 defensemen arrangement. Cane notes that some teams (Detroit, Tampa Bay, Edmonton, Washington, and Chicago, for example) relied heavily on the 4 forward/1 defenseman setup in 2014-15 and that, in general, teams that employ the extra forward on the PP tend to convert at a higher percentage. The 4F/1D setup leads to increases in Corsi For per 60 and shooting percentage for the team on the powerplay. As one might expect, the use of an extra forward also leads to an uptick in Corsi Against per 60 for the team while on the PP and a decrease in goaltender save percentage for the team while on the man advantage. In the end, Cane reasons that the approach is still a net gain. Teams using the 3F/2D post a Goal Differential per 60 of 4.9 – teams that use the 4F/1D setup post a goal differential of 6.1. Over the course of a season, this works out to 8 extra goals or 1.25 wins, which is a great return for a small change in PP tactics.
Read for yourself here.