The Launch of the Tape to Tape Project

Earlier this year, Rushil Ram, Mike Gallimore, and Prashanth Iyer launched Tape to Tape, an online tracking system that can be used to record locations of shot assists, zone exits, and zone entries. Rushil and I will be running the Tape to Tape Project in order to compile a database of these statistics with the application Rushil created. We have already had close to 30 trackers sign up from an announcement on Twitter last week.

 

 

 

Each individual will track zone exits, zone entries, and shot assists for games they sign up for. Once the games are complete, the data will be exported to a public Dropbox folder. The goal with this project is to enhance our understanding of these microstats as they pertain to coaching decisions, player performance, and wins. What follows next is a description of what we will be tracking, a brief summary of the research that describes why these specific microstats are important, and how we will be tracking these events.

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An Introduction to NWHL Game Score

In July of 2016, Dom Luszczyszyn released a metric called Game Score.  Based on the baseball stat created by Bill James (and ported to basketball by John Hollinger) the objective of game score is to measure single game player productivity.

While it’s often easy to compare players across larger sample sizes, comparing two different players’ performance on a given night can be difficult. If player A has a goal, two shots, and took a penalty, did that player outperform player B who had two assists and one shot? Game score attempts to answer that question by weighting each of the actions of each player to give us a single number representing their overall performance in that game.

Unlike Dom, whose main goal was to create a better way to evaluate single game performance, mine was to create a better statistic to evaluate the total contributions of players. There are no advanced metrics, like Corsi For percentage, or even Goals For percentage, available at this time in the NWHL. Because of this, points are the best way to evaluate players, even though other box score stats are available.

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Hockey-Graphs Podcast Episode 9: Erik Karlsson and Market Value

Chris Watkins joined Adam Stringham to discuss some of his new work and Erik Karlsson’s recent comments. Is the NHL entering a new age of superstar transition? Will the leagues best players start jumping around in free agency? Any comments are appreciated, the goal is to produce a podcast that people want to hear. Please subscribe to the podcast on iTunes!

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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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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