Complaining about officiating is an unmistakable sign of a poor sport. Only a terrible sportsman blames the referees, but let’s get real: the Caps are getting screwed on penalties against the Pittsburgh Penguins. I’m not here to spread conspiracy theories or accuse officials of malpractice; I’ve just got some cold, hard facts that may blow your mind.
Our friend Addison Huber did some number crunching on our behalf and turned up some exciting finds.
Recently, Caps PR maven Nate Ewell tweeted some interesting statistics regarding the discrepancy between penalties for and against the Capitals in games against the Penguins. Nate’s count came to 73 penalties against the Caps versus 43 against the Penguins in the last 14 games the two teams have played against each other. This information made me wonder just how unusual these numbers were compared to some sort of “average” data set.
In order to come up with an average to compare the Caps-Pens series against, I compiled two different sets of data. The first comparison was the Caps against several other teams in 14 game sets. In order to keep the time period the same as the Caps-Pens set, I limited the team selection to Eastern Conference teams, since they play with much more frequency. All the Eastern Conference teams (less Pittsburgh and Washington) were arranged in alphabetical order and numbered. I then used www.random.org to select three of those teams, which ended up being New Jersey, New York Rangers, and Tampa Bay. Penalty statistics for the last 14 games against each of those teams were taken from www.espn.com. Penalties for each team in each series were summed, then averaged to give an average for-and-against number, percent of penalties called, and average penalties called per game. That action yielded the following results: in a 14 game series against a random team, the Capitals would be expected to be called for 67 penalties, while their opponent would be called for 73 (48% and 52% of total penalties, respectively). Penalties-per-game were be 4.81 for the Caps and and 5.19 for their opponents. On average, there were 140 total penalties called in the series.
To provide another data point I again used www.random.org to select 14 games from the last 240 games played (the same period as the last 14 games against Pittsburgh) and looked at the penalty data for that random “series.” Game 1 was the first game of the 2007-8 season and game 240 was the most recent game against Calgary. The random 14 game series showed that the Caps should be expected to be whistled for 72 penalties, while their opponents would be whistled for 63 (53% and 47% of total penalties, respectively). Penalties-per-game would be 5.14 for the Caps and 4.5 for their opponents. On average, there were 135 total penalties called in the series. With a variance of about only 5% between the two data sets, I would say these numbers are a pretty accurate representation of the Caps’ propensity to be called for and draw penalties.
Comparing these penalty numbers to the penalty numbers from the Penguins “series” that Nate referenced led to some interesting results. At first glace at Nate’s Tweet, I would have guessed that the Caps were being called for penalties at a higher rate than normal. However, in a 14 game series, we would expect the Capitals to be called for 70 penalties, whereas in the Pens series they were called for 73, only a 5% increase and well within standard deviation. Looking at the penalties called on the Penguins, however, yields a much more unexpected result. While we expect the Pens to also be called for about 70 penalties, they were only called for 43, a 37% decrease, way outside a reasonable margin of error. To find the probability of this few penalties being called against the Penguins I plugged the numbers into the Poisson distribution. [Ed. note – see Appendix A below for more information regarding Poisson.] According to that function, the probability of the Pens being called for only 43 penalties is .01437%. Not that I am a frequent wearer of aluminum millinery, but it is clear that, for whatever reason, the referees are putting away their whistles against the Penguins when they play the Caps but continuing to call the Caps for penalties at the same rate. Alternatively, it could be argued that the Penguins, for some reason, play much more disciplined hockey against the Capitals. No matter what the explanation, it is obvious that the Caps should always practice their penalty kill before they play the Penguins.
For everyone who blacked out when the numbers came, the proliferations of Caps’ penalties against the Pens stretches credulity. We could spend hours guessing why the Penguins receive preferential treatment while the Capitals get the lash, or we could cast aspersions against the zebras, or we could claim the the game is fixed. But we will do none of that.
The Capitals will win or lose on their merit. Nothing else. The officials are imbued with the trust of the game, and if that trust is abused, so be it. It is beyond our ability to fix. Until the last horn blows, it is up to the team — and no other– to determine its own fate.
We leave you now with further ruminations on the Poisson distribution, as expounded by noted philologians Richard Bell, Michael Bivins, and Ronald DeVoe.