Sunday, 14 April 2019

The Long Odds of Canada’s Long Stanley Cup Drought, 2019 Edition


The Long Odds of Canada’s Long Stanley Cup Drought, 2019 Edition

April 24 Update:

Well, here it is, not even the end of April, and all three Canadian teams have been knocked out in the quarter-finals.  So, that brings the losing streak to 25 years, and the odds change accordingly.  The binomial theorem now shows odds of 0.26%.

By the way, another way to calculate this is to raise .788 to the 25th power, giving .0026 or 0.26%.  It’s quicker, but you get less information than you do from the other methods (e.g. the most likely number of Canadian team Stanley Cups during a run of 25 years). So, you should read the full blog, because there are some interesting statistical methods and data science techniques used there. ☺

April 2019

I thought I should update this blog, as two more years have passed since the last time I looked at this phenomenon.  The statistics on Canada’s long run of years without a Canadian team winning the Stanley Cup have only gotten worse.  There have now been 24 straight years without a cup – should this year prove dry as well, that will be 25.  That would be the Silver Anniversary of not winning the esteemed, and partly silver cup.

The original bowl was made of silver and is 18.5 centimetres (7.28 inches) high and 29 centimetres (11.42 inches) wide. The current Stanley Cup is topped with a copy of the original bowl, made of a silver and nickel alloy. (Wiki entry)



At least this year 3 Canadian teams made the playoffs (about what one would expect from probability theory) – the last time I looked at the drought (2016), there were no Canadian teams at all.

So, the updated question is “what are the odds of no Canadian team winning the cup for 24 straight years?”.  It turns out, that’s a very low probability event, about .0033 in usual probability terms, or 0.33%, when expressed as a percentage.  In other words, about 1 chance in 300.

One way to calculate that is via the binomial theorem.  You can look that up in a table (lots of them can be found on the internet, or you can find one in a stats textbook), or use the excel function BINOM.DIST.  The calculation can be described as “how many times would you get 0 successes in 24 trials, assuming the probability of success in any given trial was about 7/31 (actually, I used .212 instead, to reflect the changing percentage of Canadian teams in the league over the 22 years).
 


It is also interesting to see how the odds of the losing streak change, as the streak grows longer.  I calculated those odds for streaks from 1 to 25 years, and graphed the results, as shown.



As you can see, the odds of this have been quite low for a long while. 

Another way to look at this, is to calculate how much money you would win on a bet like this, as the streak increased.  The accompanying graph shows that, if you had walked into a betting shop and made that bet in 1994 for $100, you would now be on track to pick up nearly $40,000.  Obviously, betting that a losing streak would last for two decades or more, is a pretty slow way to make money, but in illustrates just how unlikely such a long losing streak really is.



You can also set up a Monte Carlo for problem, as a check on the binomial theorem result.  The procedure is:

·       Make a list of 30 teams, and fill with random numbers (use rand()).  That will represent 1 season of play
·       Make 7 of those Canadian teams, via assigning a 0/1 variable, with Canadian=1.
·       Assume that the team with the highest random number won the Cup that season.  Do this by finding the maximum randomly assigned number (use ax(list)).
·       Assign a 1 in another column to the team that has the maximum value (use if(team=max_random, 1, 0) .
·       Multiply this column by the Canadian/NonCandian column, and put the result in a new column.  If the winner is a Canadian team, that column will total to 1, otherwise it is 0.
·       Now, you have determined whether the Monte Carlo has a Canadian team winning the Cup in Season 1.
·       Repeat that 23 more times, to simulate 24 straight seasons.
·       Calculate the sum of the Canadian winners over the 24 simulated seasons.
·       Test to see how often that comes up to 0.

When I did this, I found only 1 occasion in my 24 season streak tests, out of 1000 trials, where no Canadian team won the cup during that stretch.  That’s somewhat less than what the Binomial Theorem estimate gave, but with such small probabilities, it can take a lot of runs for a Monte Carlo and a closed form solution to converge.  Still, the results are pretty close, and both demonstrate just how unlikely this finding is, on statistical grounds.

Note that most likely result, based on the Monte Carlo, is between 4 and 7 Canadian team wins during a 24 year stretch.  That makes sense, as it corresponds to the percentage of teams in the league that are Canadian based.



So, we have awfully long stretch of losses occurring.  It strains credulity to consider this to be merely bad luck.  Some other theories have been propounded:

·       It’s related to the Canadian dollar.  But that doesn’t work, as the Canadian dollar has varied considerably during this time period, sometimes being lower and sometimes higher than the U.S. dollar.
·       Another theory states that hockey players can’t stand the pressure of playing in the Canadian cities, where the sport is taken very seriously by the fans. Therefore, the players choke, basically.  That theory seems unlikely – after all, professional athletes have come through a grueling system of training and preparation to make it to the big leagues.  They know how to handle stress.

So, the only theories remaining (that I can think of), are:

·       It’s a conspiracy - the league helps the U.S. teams win (say, via referee decisions or Board of Governor actions), to help out teams in the more financially uncertain U.S. marketplaces.  But, that seems like a difficult to conspiracy to actually make work, as the league simply doesn’t have that sort of control over the referees or the owners.   
·       Economics  - Canadian teams can make as much money losing as they can winning, so they don’t manage their business affairs with winning as a significant priority.  Indeed, playing rope-a-dope with Canadian fans might be an optimum strategy, keeping player payrolls relatively low, while holding out “wait until next year” hopes for the hockey-mad fans, who will show up, come what may.

Perhaps the Canadian sports media will give another go at this.  In recent years they have nodded towards the strange phenomenon each spring, almost as a ritual now.  Their explanations are usually pretty lame, and they also reveal their weakness with statistical reasoning during these efforts.  Not that I expect much from a journalist, when it comes to math.

At any rate, the Great Canadian Stanley Cup Drought is truly a conundrum.

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If you have some spare time, possibly due to lack of interest in the NHL playoffs, you might want to consider a nice road trip, exploring the non-hockey contrasts between Canada and the U.S..  If so, then “On the Road with Bronco Billy” is definitely your book. 

Sit back and go on a ten day trucking trip in a big rig, through western North America, from Alberta to Texas, and back again.  Explore the countryside, learn some trucking lingo, and observe the shifting cultural norms across this great continent.  There's even some hockey playoff talk (Oilers-Denver and Oilers-Dallas), for those nostalgic for Canadian playoff representation.

It’s on Amazon (ebook), for a mere 99 cents (U.S.).






Or, if you want to continue contemplating mysterious runs of luck, you could try “A Dark Horse”, which concerns the troubling run of good luck that a (fictional) horse player experiences.
Also on Amazon (ebook), for 99 cents (U.S.).



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