The Hockey-Graphs Podcast Episode 3: Expansion Draft and GM Rankings

Welcome back to The Hockey-Graphs Podcast! Our third episode showcases Chris Watkins and Carolyn Wilke‘s recent articles; The 2017 NHL GM Report Cards (Parts 1, 2 and 3. Given the leaks that came out prior to the expansion draft; what is Las Vegas’ strategy? Are good general managers always good or do they excel in some areas and struggle in others? We discuss those questions and more in this episode of The Hockey-Graphs Podcast. Any comments are appreciated, the goal is to produce a podcast that people want to hear. Please subscribe to the podcast on iTunes!

Who You Calling Weak? Draft Class Variance

This year’s NHL draft class is weak. I don’t follow junior prospects closely, but that’s what I’ve heard from more knowledgeable sources. It’s a fair claim; Nolan Patrick and Nico Hischier seem talented but not among the game-changing talents that have recently been drafted first overall.

However, it’s harder to judge the draft class past the very top. Scouting is hard, especially for hundreds of prospects across the world. It’s possible that while there is no clear star in the draft class, the rest of the draft is as strong as ever.

That would have big implications for draft strategy. The conventional wisdom is that teams may trade more picks this year because they believe the weak draft class makes the picks less valuable. But if the draft is typical after the first few picks, that would be a poor use of assets.

We don’t yet know how well this year’s draft class will do in the NHL. But, we can use historical data to ask questions that establish expectations: how well does each draft class typically perform, and how much does this vary by year?

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The Hockey-Graphs Podcast Episode 2: Risk Aversion and the Draft

Welcome back to The Hockey-Graphs Podcast! Our second episode showcases Namita Nandakumar‘s recent articles; Exploiting Variance in the NHL Draft and Who’s Getting Drafted This Year?. Namita and Adam discuss: draft theory, risk aversion, player potential, central scouting rankings and how to best apply her research moving forward. Any comments are appreciated, the goal is to produce a podcast that people want to hear. Please subscribe to the podcast on iTunes!

FQG: Cumulative Hits in the Conference Final

May-15-2017 21-24-14 phaneuf hits guentzal

Throughout the playoffs (quarterfinals, semifinals), I have analyzed whether a team’s hits for and against were indicative of their success. Studying a team’s Corsi for percentage per game and expected goals for per game alongside their cumulative hits can help us spot high-level trends.

We’re seeking to determine the accuracy of the narrative that many hockey traditionalists love – that a team must increase their hitting to succeed in their quest for the Stanley Cup. This has been studied in recent seasons, including 2014-15 season, 2015 playoffs, and 2016 playoffs, yet no decisive correlation was found between a team’s increased hitting and success. So far in the first two rounds of the playoffs, this seems to hold true.

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Should teams play with 4 forwards when they’re down late?

Tl;dr

  • There is some evidence to suggest that teams should play with 4 forwards when trailing late in a game.
  • The timing of when to switch to 4 forwards is dependent on how large an impact the switch has on goal scoring rates, however even with a low impact on goal scoring, using 4 forwards still makes sense.

One of the weird things about sports that I find fascinating is how often coaches and players seem to go out of their way to avoid having a negative impact on the game, even at the expense of potential positive impacts. People often seem to prefer to “not lose” rather than to win, which can result in sub-optimal decision making, even in the presence of evidence to show that the correct decision is not being made.

There are many examples of this across sports, but the biggest two in hockey are pulling the goalie and playing with 3 forwards on the power play. Analysts have been arguing for many years now about why teams should pull their goalies earlier, but it’s only been in recent seasons that teams have become more aggressive in getting their netminders out earlier.

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Friday Quick Graphs: Update on Predictive Relationships

Screen Shot 2017-05-18 at 1.27.20 PM.png

The above graph is a slight variation of the method employed by JLikens (Tore Purdy) six years ago, almost to the day. The variation being the method I used was extremely simplified. All I did was look at the correlation between each metric for the first 20 games with goals for the next 62 games in the season, with both variables being 5v5 and adjusted for score and home/road venue. I also skipped the lockout shortened season for insufficient games.

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The Hockey-Graphs Podcast Episode 1: Team Play With Ryan Stimson

Welcome to The Hockey-Graphs Podcast! Our first episode showcases Ryan Stimson‘s recent article; Identifying Team Playing Styles With Clustering. Ryan and Adam discuss: how the piece came about, the methodology of the clustering, the pros and cons of each individual cluster and how to use this data to better team results. Any comments are appreciated, the goal is to produce a podcast that people want to hear.

Reach out on Twitter! The podcast will be on iTunes within the next few weeks, until then please listen through Soundcloud!

How Indicative are hits in the 2017 Stanley Cup Playoffs: Semifinals

After the conclusion of the 2017 Stanley Cup Quarterfinals, I looked at whether a team’s hits for and against were indicative on their play. By looking at a team’s Corsi for percentage per game and expected goals for per game, against their cumulative hits as their first round progressed, it could be observed whether a team’s production dropped due to being outhit.

As it was explained in the first part of this series, many hockey traditionalists point to an increased number of hits as a necessity to compete for the Stanley Cup. There is a preconceived notion by some hockey minds that a team will become worn out if they are consistently outhit in the playoffs and subsequently will not be able maintain their production. However, in the 2014-15 season, 2015 playoffs, and 2016 playoffs, no decisive correlation was found between success and hits.

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