Hockey Analytics Data Sprint Wrap Up

On Saturday, November 4th, we hosted the first ever Hockey Graphs Analytics Data Sprint.  The idea was teams had 6 hours to take raw data and do something interesting with it as a trial for the Vancouver Hockey Analytics Conference. Local teams met up at La Casita here in Vancouver, but we also had online participants as well.

Thanks to all of the people who helped put it together, and thank you to all those who participated, especially those who travelled from as far away as New York.

In this post we link to the finished results and you can see the winners.  Their work is in a github repo which you can use for your own data analysis!

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Save The Date: VanHAC 2018!

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Hockey-Graphs is once again excited to be co-hosting the Vancouver Hockey Analytics Conference for its third year! We will be working with the Vancouver Canucks, Simon Fraser University and the great team at CanucksArmy.com.

This year we’ll have a 3 day conference, with 2 days of talks, tutorials, keynotes and great discussions. There will also be plenty of social events throughout the weekend.

All knowledge levels are welcome.  If you are interested, you are more than welcome! Nobody will be turned away, everyone is encouraged to attend.

Date: March 2nd to 4th, 2018

Location: Downtown Vancouver, Canada

Website: https://hockey-graphs.com/events/vanhac18/

The Call for Presentations is currently open with a deadline of January 8th, 2018.  See the website for more details or go here to submit your talk. 

Registration has yet to open as we tabulate the final costs to host the venue, among other factors. Check back here or on Twitter, or add yourself to our mailing list, for more information on when it will open. (Note: Expect participants to be capped at around ~175 people.)

Watch the VanHAC page for updates as they are released!

Hockey-Graphs Podcast Episode 8: Market Efficiency and Diminishing returns

Shawn Ferris joined Adam Stringham to discuss some of his work over the last year including: his piece on whether shot parity is increasing, a look at how teams relying on high percentage changes are less consistent in their expected goal output and some of his upcoming works. Any comments are appreciated, the goal is to produce a podcast that people want to hear. Please subscribe to the podcast on iTunes!

#RITHAC 2017 Slides & Video

Yesterday, the third annual Rochester Institute of Technology Hockey Analytics Conference was held. Below are links to the slides for each presenter, as well as links to a stream of the morning and afternoon sessions. Please refer to this post for the time of each person’s talk or panel. More detailed recaps are undoubtedly coming from people, so this is simple a reference for streams and slides for those that missed the event or would like to revisit certain talks.

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About that Flyers challenge last night…

Embed from Getty Images

Last night Dave Hakstol and the Flyers were the first team to get burned by the NHL’s new offside challenge rule. With a one-goal lead over Nashville and just 2:41 left in the 3rd period, Philadelphia was dinged for not one but two minor penalties at the same time. And on the ensuing 5-on-3 power play, Scott Hartnell banged in a loose puck to tie the game up.

https://www.nhl.com/video/embed/hartnells-late-game-tying-goal/t-290860626/c-53362803?autostart=false

Philly, however, decided there was something not quite right about Hartnell’s goal. They thought that Filip Forsberg may have snuck into the offensive zone just slightly ahead of the puck on the zone entry that preceded the tying marker. The Flyers decided to challenge, hoping that video review would negate the Preds’ goal and put them back on top with just under two minutes to play.

When news first came out of the league’s proposal to change the rules, there was a lot of skepticism that it would act as much of a deterrent to frivolous challenges. While no coach wants to see their team go on the penalty kill after conceding a goal, the odds were still stacked pretty heavily in favour of challenging even in low probability scenarios. In a normal even-strength situation, your probability of success doesn’t need to be all that high in order to make a challenge worthwhile, in fact you’re safe challenging a lot of the time with less than a 25% certainty of success.
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Fear and Loathing in Las Vegas: An analytical deep dive into the Vegas Expansion Draft

Despite the aura of calm projected by Golden Knights owner Bill Foley, his nascent desert franchise is already on the clock. The recent announcement that the Oakland Raiders will be moving to Las Vegas in 2019, has already undermined Foley’s plan to be the only show in town. If the Golden Knights don’t win over the Vegas fanbase in relatively short order, it could prove almost impossible for hockey to get ever get a foothold in Sin City.

As a result, the team faced a variety of difficult decisions going into the 2017 expansion draft. On one hand, the team could try to win immediately with aging veterans like Eric Staal, which would allow them to establish a foothold in the market, but also put them at risk of years of mediocrity as older players lose their fights with Father Time. On the other hand, the team could tank in the hopes of finding stars at the top of the draft, but the resulting efforts could further exacerbate the fan bases preference for the incoming NFL juggernaut.

In order to evaluate the quality of the selections of GM George McPhee, I viewed each pick as a “trade” and applied prototype of a “Trade Machine” to look at each selection, given the choices available. For example, Vegas chose Clayton Stoner and Shea Theodore from the Ducks over Sami Vatanen, which means, in essence, the selection was a trade for Theodore and Stoner for Vatenen straight up. After looking at all 31 selections, I compared Vegas’ actual roster to one consisting of an optimal roster calculated using DTMAboutHeart’s GAR statistic. The results are below.

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How certain do you need to be on an offside challenge?

Offside challenges are, to say the least, a controversial topic. While many have advocated for the benefit of getting the call right even at the cost of a delay in the game, it’s almost indisputable that the introduction of the offside challenge has slowed down the flow of the game. Over the past two years, coaches have challenged any play that was remotely close with the hopes of getting lucky on the video review, to the dismay of basically anyone other than replay technicians.

Those spurious challenges are one reason why the NHL modified the rules around coach’s challenges yesterday. Starting next season, instead of a failed challenge simply resulting in the loss of a team’s timeout, clubs will now face a 2 minute penalty for losing an offside challenge. Upon hearing of this change many fans were apoplectic, complaining that this rule change could bury teams who were already reeling from giving up a goal against, and would severely limit the willingness of coaches to challenge even legitimate missed offside calls.

Fan reaction notwithstanding, however, the question coaches should be asking is whether they should be changing their approach in response to the new rules. The threat of killing off a penalty for a failed challenge may seem like a big deal, but it’s important to note that teams only score on roughly 20% of their power play opportunities. Fans will surely remember when a failed challenge leads to a power play goal against, but there will certainly be occasions when the potential gain from overturning your opponent’s goal outweighs the risk.

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The Hockey-Graphs Podcast Episode 6: Mock Off-Season Part 2

Adam Stringham was joined by: Chris WatkinsNamita Nandakumar, Garik16 and Shayna Goldman to redo the 2017 NHL off-season!

Here are the rules that we used for the mock off-season:

  • The rosters were rolled back to the start of free agency.
  • The Salary Cap has gone up 10% to 82.5M
  • Max contract length is 5 years
  • There are player and team options (so Connor McDavid could sign a 4 year contract with a player option for the 5th year)
  • All no trade clauses are void, and teams can go over the cap to sign their own players (up to $90M)
  • There is no compensation for offer sheets. the team can either match or the player walks for free.

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Hockey-Graphs Mentorship Program

Asmae Toumi, Editor-in-Chief
atoumi.cu@gmail.com


Hockey-Graphs
Mentorship Program

 

Overview

Inspired by Python’s Core Mentorship Program, we believe the best way to increase diversity in the hockey analytics community is to connect experienced and dedicated mentors with interested beginners. The aim of the Hockey-Graphs Mentorship Program (HMP) is to inspire people from various backgrounds, especially underrepresented persons, to contribute to the flourishing hockey analytics community.

This is where HMP mentors come in. Mentors will provide beginners with the support, guidance, and encouragement they need to 1) learn about statistics/analytics and 2) use that knowledge to answer questions pertaining to hockey. In addition to 1-on-1 mentoring, mentees will be given a tailored guide with additional resources to strengthen their knowledge and skills. Mentees will also receive priority access to various HMP-sponsored workshops and social events hosted at major hockey analytics conferences.

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