A Few Thoughts on a New Hockey Helmet Safety Study

I’m seeing a lot of media attention around the work of Drs. Stefan Duma and Steven Rowson of Virginia Tech. They have a study coming out in the journal Annals of Biomechanical Engineering which tested 32 hockey helmets on their ability to reduce concussion risk. The authors have also developed something known as the STAR rating system for hockey helmets and maintain a website that shows how the helmets performed. The star system ranges from 0 stars (not recommended for use) to 5 stars (best available).

ESPN has a great write up http://espn.go.com/espn/otl/story/_/id/12564082/virginia-tech-study-hockey-helmets-finds-many-unsafe and includes a video which shows their talk with Dr. Duma about his research, and with Bauer Hockey to get their response on the findings. Virginia Tech also has a write-up which describes the project https://www.vt.edu/spotlight/impact/2015-03-30-hockey/ratings.html. For those interested, the hockey helmet rating site can be found here http://www.beam.vt.edu/helmet/helmets_hockey.php.

I haven’t had a chance to read the full study at this point, but a few things from their findings certainly stand out for me. First is that the top rated helmet, the Warrior Krown 360, received 3 stars. It is the only three star helmet (3 stars rates “good”) among the 32 helmets. This is not a great finding for hockey helmets. The authors have a similar website for football helmets and they list numerous football helmets with 4 and 5 star ratings. As well, 9 of the hockey helmets were deemed 0 stars and so were not recommended at all. For parents with kids in minor hockey (or those considering putting their kids in the sport) the poor performance of hockey helmets certainly won’t add to the allure of the game!

A second thing that stands out is how poor the CCM Resistance and Bauer Re-Akt 100 helmets perform relative to cheaper helmets within their own brand! My oldest son has the CCM Resistance (and previously had the Bauer Re-Akt). These helmets have been marketed based on them being the latest and greatest in protecting the head (with a price tag to match). So seeing their lesser (and cheaper) helmets perform better (at least according to the metrics used in this particular research) will be sure to raise some eyebrows of those that purchased the more expensive helmets. For instance the Bauer 2100, which is listed as US$34.99, ranks better than the Bauer Re-Akt 100, which is US$269.99. I am very interested to hear how companies like Bauer and CCM respond to this study (My understanding is the CCM Resistance helmet was designed in collaboration with researchers at the University of Ottawa, and so I especially await their response).

Lastly, as a hockey parent, I am always happy to see people working in this area. As a researcher I look forward to reading the academic paper to get a better sense of their research design, and I hope to learn more from the work that follows that builds on or critiques the work of Drs. Duma and Rowson.
RAC

What Happens When We Use Analytics Tracking on 8 Year Olds?

A recent video by USA Hockey brings together two of my current interests, hockey analytics and minor hockey.* One of the things coming from the analytics movement is the development of technology to better track the actual game play of NHL players. Recently we saw some of this technology with the 2015 NHL All Star game which incorporated computer chips in the jerseys of the players. This type of technology has been generating a lot of attention as it may improve and change our understanding of hockey performance (see my February 18th blog for more on this).

While this sort of technology applied to the NHL seems really cool, the use of this technology to better understand the game for young kids and how to provide an environment that maximizes their development and interest in the sport could provide important insights. That’s where this recent video comes in. USA Hockey took a group of kids from Detroit’s Little Caesars 8U team and used microchip (RFID ) technology to track the kids in full-ice as well as half-ice and cross-ice game play. They measured things like how often they possess the puck, number of shots, pass attempts, etc and looked at how these changed across different ice sizes.

The findings show how much kids benefit from the smaller ice-surface play. This result probably isn’t that surprising, as I know many who have argued for smaller ice surfaces for young kids anecdotally, but this video provides data which supports this. For skill development, this is great to know, and for keeping kids interested in the game and not getting turned off at an early age, this also proves important.

In Winnipeg, games at 5 and 6 years old are full ice games. I’ve had two kids go through this and I’ve experienced it with a kid who skated through everyone scoring 5 or 6 goals a game (and so possessed the puck for most of the game), and I’ve experienced it with a kid that never got to touch the puck and would quickly become frustrated or lose interest during the game. Both kids have always really enjoyed 3 on 3 at a place in Winnipeg known as The Rink. This is partly due to the unstructured nature of 3 on 3, but also due to the fact that The Rink ice surface is much smaller than a full ice surface. The kids therefore get many more touches with the puck, and are always engaged in puck battles and pressure due to the small quarters, in line with the points raised in the video.

My understanding is that Hockey Manitoba is moving towards games using less than full ice for 5 and 6 year old kids, and I look forward to seeing how my third son experiences the game this way when he starts.

If you have a few minutes, definitely give the video a watch.
RAC
*Thanks to Glenn Yates and Randy Aitken for both bringing this video to my attention!

Learning Hockey Analytics the Hard Way

Over the past year I’ve increasingly been hearing words such as Corsi, Fenwick, PDO, and Zone Starts when assessing NHL player performance. As someone interested in hockey as well as being a professor of sports economics I increasingly thought I should take the time to learn what these things are all about.

As many of you know, wanting to learn something, and finding the time to do it, can be two different things. I started teaching a class in sports economics a few years back as a way to get myself to finally learn about this area of the economics literature, and so I figured if I put a few classes of hockey analytics on my sports economics syllabus, then I’d have to teach it (and hence learn it) or else risk embarrassment when I didn’t deliver.

This isn’t a blog about responding to incentives though, it’s about highlighting a few of the interesting things I came across in my reading. First thing is that there are a lot of sites available with data for these different hockey metrics. These sites are a great way to learn what the main measures are that people are using, and they usually contain a description of the measures somewhere on the site. Sites such as Behind the Net, Progressive Hockey, and Hockey Analysis are great places to start. As well, the NHL on its NHL.COM website will be adding a range of hockey analytics data (around 30 different measures) soon, and so is something to keep an eye on as well.

In terms of readings for hockey analytics, I didn’t rely on academic articles so much as what the hockey press and related bloggers have written in this area. Benjamin Wendorf at the Hockey News has a short but informative introduction to hockey analytics, as does Sean McIndoe and Steve Burtch . Coming from these articles you get a sense of what measures people use, how they have changed the way fans and team officials view player and team performance, and give a sense of the things to come in hockey analytics.

The Burtch article is especially interesting as it spends some time discussing the psychology of how humans make decisions, and how mental short cuts and small sample sizes can all lead to poorly made judgements and decisions, leading the reader to better understand how the new approach to hockey analytics can help partially overcome some of these problems.

Something mentioned in McIndoe’s article and seen recently with the NHL All-Star Game is the use of microchip technology in the sweaters of players as well as puck to provide real time data on things like player speed, how fast the puck is shot, possession time, or whether the player enters the zone with possession. As well through the reliance on microchips, we should see increased standardization of the data itself. For more, Alex Prewitt of the Washington Post has a great article on what microchip technology might mean for player tracking.

I’m still a bit of a beginner with these things but I will be teaching a 3 week course on sports economics in May and so will be sure to update this blog with what’s new at the time in this evolving area of hockey assessment.
RAC

The CAUT Investigation

Warning: this blog is not about hockey. Just something I need to get off my chest.

As noted in today’s Winnipeg Free Press article, the CAUT has released the report of its investigation into alleged violations of academic freedom at the University of Manitoba’s economics department, where we work.  The report was damning in its opinion of the department, and recommended a number of drastic measures that would steer the department in a direction that the majority of faculty are against. Many of the points raised in the report are inaccurate and misleading, but this is to be expected when the CAUT had no access to confidential documents and could not compel university faculty to be interviewed. As a result, the report is based on the opinions of a small minority of the department who agreed to the investigation. That the CAUT released such an obviously biased, one-sided report should raise questions and outrage from all of us whose union dues are being spent to fund such activities.

Although I do not wish to give credibility to the report by spending too much time criticizing it, there are a couple of points I wish to raise. First, the WFP article states that “CAUT claimed university president David Barnard urged economics faculty members not to meet with investigators and some professors subsequently refused to talk to them.” I did not participate in the CAUT investigation. To say that some professors refused to talk to the investigators is an understatement. The CAUT interviewed only seven of the current slate of 24. My choice to not participate was due not to advise given by senior administration, as was alluded to in the WFP article. I did not meet with them because I believed my participation would be fruitless. Knowing the source of the allegations, and the agenda of the CAUT, it was my opinion that the outcome of the report was clear before the investigation even started.

The WFP statement that heterodox economists are, in lay terms, those who “think outside the box” is lazy journalism. There are many people within mainstream economics who ‘think outside the box’ and move the field forward. Economics is not static and the working definition of what is inside and outside the mainstream is constantly changing.  However, within the department those who claim to be heterodox have a very specific definition of the term – heterodox is limited to those fields in the JEL codes B5.   In practise, we have no Austrians on faculty and the feminists do not align themselves with the heterodox group. So the view of heterodox in the department is actually very narrowly represented by Marxists and Institutionalists.

The investigators write that “among the panoply of academic economists, and in the Department that we are investigating, we discern three groups. (1) Those who practise and embrace heterodox economics; (2) those who practise mainstream economics but feel that heterodox economists have an important place in the profession; and (3) those who…feel that practitioners of heterodox economics have no place and should have no standing in the profession.”

I would place myself in group (2), with a caveat. As has been stated many times by many on the so-called ‘orthodox’ side, many of us believe that heterodox is a valid and important field in economics, but no more or less valid and important than the other fields represented in the department. That is the philosophy that drives my votes in department meetings on hiring and curriculum, and I believe this is a common view among faculty members. This viewpoint is different from the direction of the department in decades past, when faculty members considered heterodox economics to be of higher standing than other fields. In recent years, our faculty have voted to hire more mainstream economists in fields such as applied microeconomics, macroeconomics and econometrics, where we needed faculty. We have voted to increase the undergraduate and graduate requirements of theory, econometrics and math to bring our programs in-line with the rest of the discipline. But, we also voted to maintain the requirement of Honours students to take 6 credit hours of history of economic thought and 3 credit hours of alternative (read: heterodox) macro. Our union (UMFA) will argue that departments should have the right to self-govern on curriculum and hiring, that the faculty within a discipline are best equipped to determine the academic path of the department. To this end, the union should have clearly defended the department faculty votes to CAUT. They did not. Apparently our rights to self-govern are defended only when the results of the votes are consistent with the views of the union staff.

The WFP picked up on a section of the report that concerns interactions with graduate students. The WFP writes that “…orthodox members of the department behaved in ways that discriminated against doctoral students being supervised by heterodox economists,” the committee concluded. “This included treatment at oral examinations, advice about potential areas of study, funding decisions, and advice that their choice of heterodox supervisors was unwise in terms of their future careers.”

The statement that faculty were biased in their treatment towards students in funding and examination situations is a serious accusation. I cannot imagine that the CAUT has any factual evidence to make such a claim, since they did not have access to confidential documents and did not speak with the graduate chair. I have certainly never been aware of any such discrimination. To the other point, that advising a student that choosing to write a heterodox dissertation would be an unwise career move – well that is simply good advice. I don’t recall ever actually saying this to a graduate student, but if one had asked I would certainly tell them that unless they had a deep passion for writing a Marxist dissertation, if their goal was to land an academic job in a North American university, this would not be a good move. I was given the same advice in graduate school when I flirted with the idea of doing an economic history dissertation. I was told that the market for this field is thin and that I should focus on another topic until after tenure and then I could indulge in this area of research. The professor who gave this advice had earned a Nobel Prize in economic history, so it was not given out of disdain for the field but rather meant to be informative about the current economic PhD market.  I would absolutely give the same advice with the same motivation.

To end, it is hypocritical of the CAUT to make recommendations on the hiring and curriculum decisions of the department – the recommendations include that we must hire 3 heterodox positions in the next few years, that the head of the department should be replaced immediately and that any new head should be committed to maintaining two broad traditions in the department. They outline the composition of search committees and insist that our department council meetings should be chaired by an external academic. All this in the name of ‘academic freedom.’ As one twitter commenter (@alexusherHESA) noted “I think Academic Freedom as an intelligible concept in Canada, may just have jumped the shark.”

JRC

Elasticity of Demand and Manitoba Minor Hockey

Following an altercation in the U.S. last year, a Winnipeg couple was penalized with a one-year suspension from minor hockey. Their son could register to play with Manitoba Hockey, but the parents would not be allowed to attend any practices or games. Instead, the couple chose not to register their child for minor hockey, and the Winnipeg Free Press reports that this response surprised members of the discipline committee. That they were surprised at this outcome suggests that they are underestimating the elasticity of demand for minor hockey in Manitoba.

For those of you without first year economics, elasticity of demand measures how sensitive consumers are to the cost of goods. A good that has few alternatives (e.g. milk) has an relatively inelastic demand – an increase in the price will result in only a small reduction in the quantity demanded, since consumers have few other options. A good that has many alternatives (e.g. a certain brand of beer) has a relatively elastic demand – an increase in the price will result in a large reduction in the quantity demanded, as consumers move to alternatives.

Hockey Manitoba believed that if they raised the cost of minor hockey for this couple, they would still enroll their son in minor hockey. This suggests that they believe that the demand for minor hockey is relatively insensitive to cost (read: inelastic demand). If the parents resided in a small town, this may have been the case. But in Winnipeg, there is an ever increasing number of options available to Winnipeg hockey players during the winter months – private skills camps and three-on-three leagues, for example. In addition, spring hockey is gaining in popularity and lies outside Hockey Manitoba’s jurisdiction.

This case should serve as a lesson to Hockey Manitoba – demand for winter hockey is becoming more elastic. There is no monopoly on winter hockey. With increasing options to parents, Hockey Manitoba will have to be more conscious about the costs of minor hockey and remember that they have viable competitors.

JRC

Evaluating police patrols at minor hockey games

I have taught the first year university course “Introduction to Microeconomics” for ten years. My one goal in the very first class each year is to instill in the students one key principle of economics – nothing is free. There is opportunity cost associated with everything we choose to do and we must always consider alternatives when deciding how to allocate our scarce resources. Further, when considering costs and benefits, we should focus on the marginal (additional) costs and benefits.

I was reminded of this when I read today in the Winnipeg Free Press that police officers from the Winnipeg Police Services community relations department will be dropping in on minor hockey games during the year. Their goal is twofold – first, to educate parents about fair play and respect in sport and second, to provide a deterring presence against abusive behaviour. Comments from WPF readers alternated between those thinking this is a great idea, and those commenting that it is a wasteful use of police resources.

Is this a good use of the city’s resources? To answer this, we need to ask whether the marginal benefit of the police presence at the rinks outweighs the marginal cost. Consider the first goal – education. One parent from every family in Winnipeg minor hockey was obligated to complete a one-hour on-line course in Respect in Sport before they could register their child this year. Will the police be handing out pamphlets to anyone who has not already been made aware of the expectations of parents? I don’t think so. In terms of the second goal, although they gain a lot of media attention, there are a handful of incidents each year that lead to abusive behaviour. Will a police officer curb a hockey dad from yelling instructions to his son during the game? Should they? While it may not be good parenting, incidents reaching the level of negative behaviour that would justify police intervention are rare. It is difficult to believe that there will be a high marginal benefit of the program.

Perhaps the marginal cost of the arena visits is also low, I’m not sure. The question is, what would these officers be doing if not at the rinks. They are part of the community relations department so likely they are not out patrolling high-risk areas, but there is an alternate use of their resources. To properly evaluate whether there should be police officers at the rinks, one needs to know this information. My gut reaction is that monitoring hockey parents can’t be the best use of resources, but in the end it will all be left to speculation.

Unfortunately we will never be able to measure the costs and benefits, never be able to tell if the programs are successful. Public policies should be designed in a way that allows for their evaluation. In this case, though, both programs – the obligatory Respect in Sports program and the police arena patrols – are rolled out in the same year. If there is any measurable reduction in abusive hockey behaviour, the source of the reduction will be unknown. For this reason it is likely that we will continue spending resources on both programs without ever knowing if either is beneficial.

JRC

Does Defense Win Championships?

With hockey underway again I’ve been spending a lot of time hanging around the local arena watching my kids play, and an old mantra keeps springing up – “Defense wins championships”. A widely held belief is that defense wins championships and in hockey the way to win is to build from the net out. Upon hearing this, my first thought was that I’ve actually read something on this before and I went to track down where. I remembered that this cliché isn’t necessarily true, even if it seems logical.

Tobias Moskowitz and L. Jon Wertheim have a great book titled “Scorecasting: The Hidden Influences Behind How Sports Are Played and Games are Won” (info on this book can be found via their website: http://scorecasting.com). It’s a nice book for those interested in using data to better understand sports, and is full of chapters where the authors go out and empirically test beliefs widely held among sports fans. One of these is whether defense wins championships. The authors examine all 4 major North American sports (NHL, NBA, MLB, NFL) and find that defense is no more important than offense. Winning games requires either great defense or great offense, and if you are really lucky…both!! More on this work (as it pertains to the NFL) can be found on a guest spot they did for Freakonomics (http://freakonomics.com/2012/01/20/does-defense-really-win-championships/).

Reading this book led me to search for more on this topic, specifically as it pertains to hockey, and I came across a great website that marries hockey with data. The Department of Hockey Analytics (http://www.depthockeyanalytics.com/) is a website developed by IJay Palansky, Phil Curry, and Ian Cooper. Their recent article in the Toronto Start “In the NHL, Defence Doesn’t Actually Win Championships: Hockey Analytics” pretty much answers the question right in the title. http://www.thestar.com/sports/hockey/2014/05/29/in_the_nhl_defence_doesnt_actually_win_championships_hockey_analytics.html

The authors look at this question a few ways, and I’ll leave the details of this article to the reader, but two things stood out for me. First, when looking at who won the Stanley Cup since 1980, 5 times the team with the number one defense during the season won, while 5 teams with the number one offense won. So no clear winner here in terms of defense vs. offense. Second, using a probit analysis to estimate the impact of defense and offense on winning semi-final and final playoff rounds from 1980 to 2013, the authors found that offense contributed more than defense to the likelihood a team would win (defense does matter, just not as much as offense).

So what’s the take away from all of this? Well two things. First, with this question specifically, defense is important, but so too is offense, and neither really dominates the other. As Palansky points out, goal differential is what wins and this can be achieved by scoring lots or giving up little. Second, is the broader issue of sports mantras. We hear them all the time, but the next time you hear one presented as fact, ask yourself…I wonder what the data says about this!

RAC