The NHL postseason is a crazy time. While you rarely see a No. 8 seed beat a No. 1 seed in the NBA, it happens more often on ice. So -- if we look at previous upset models, what can we learn about the 2010 postseason pucks dance? That's what Puck Prospectus is out to explain. This article focuses on the Western Conference.
Let's say someone asked you to figure out the probability of a hockey upset in the playoffs based on the difference in points between two teams in the regular-season standings. You'd probably say that teams with the same number of standings points would each have a 50 percent shot at winning the series. As the gap in the standings increased between the teams, you'd give the underdog a smaller and smaller percentage change of winning. Makes sense, right?
It did to me as well, but when I started analyzing the results of every first-round series since 1980, I realized I was wrong. The odds of an upset actually stabilize at just under 40 percent, regardless of the size of that gap in the standings.
If the gap is between zero and four points, the probability of an upset is 37 percent. If it's between 20 and 24 points, that probability increases only a little -- to 39 percent. In short, the odds of a low seed pulling an upset are actually better than you'd assume.
Now, how does that apply to the 2010 playoffs?
Dividing all 208 underdogs since 1980 into four groups based on both their regular-season scoring and their opponent's scoring relative to the league average, we find that defensive-minded teams have a noticeable advantage over the others. It stands to reason that an unexciting Jacques Lemaire-style team that plays a defensive system would be more likely to pull off an upset, because catching a break or getting a lucky bounce means a lot more to a team in a low-scoring game than in a high-scoring contest.
Teams that play a style you'd classify as "high-scoring with good defense" can pull upsets 42 percent of the time (logical); teams that are "low-scoring with good defense" hover at a 40 percent upset clip. On the flip side, if you're "high-scoring with a bad defense," you'll score an upset only 28 percent of the time, historically; it's the same percentage for "low-scoring with a bad defense."
Looking at the underdogs in this year's postseason, good defensive teams like the Boston Bruins and Detroit Red Wings are more likely to upset, whereas weaker ones like the Ottawa Senators will have uphill battles.
What about special teams? Among the favorites, those that had above average power plays relative to the league average were 9 percent less likely to be upset than those that didn't. Again, it stands to reason a team that can make an aggressive underdog pay for pushing too hard would be a little less likely to be sent home early. In this case, think twice before betting against the Washington Capitals, Vancouver Canucks or San Jose Sharks, but take a good look at the Vegas line for the Phoenix Coyotes.
Let's look at the four Western first-round series and see what we can learn.
Colorado Avalanche vs. San Jose Sharks
Historical chance of an upset: 30 percent
Closest equivalent: The 1997-98 Coyotes, who lost 4-2 to the Stanley Cup winning Red Wings. We have to go to the seventh-closest match to find an upset, when Edmonton upset Colorado that same season.
By virtue of a red-hot start, the Avalanche surprised everyone by making the playoffs despite their eventual regression to the mean. Colorado is consequently the coldest team in the postseason -- overall they're just a bit above average offensively and about average in all other areas. San Jose, on the other hand, is safely above average in almost every department; the Sharks do tend to take a few too many penalties, though.
The Oilers managed to surprise the 1998 Avalanche when Curtis Joseph decided almost unilaterally that the Oilers would see the second round. To pull off an upset this year, Avs netminder Craig Anderson would have to set the table by finding his early-season magic, leaving the unpredictable potential of the young Avs stars like Paul Stastny, Chris Stewart, Matt Duchene, T.J. Galiardi and Peter Mueller to serve San Jose the unpleasant dish.
Nashville Predators vs. Chicago Blackhawks
Historical chance of an upset: 30 percent
Closest equivalent: The 2001-02 Montreal Canadiens, who upset the Boston Bruins 4-2. Boston took more penalties than Chicago does and had a less effective power play, so an upset would be a tougher feat for Nashville.
The Predators keep the scoring below league average at both ends, which can be a good sign for an upset. They take relatively few penalties -- but their special teams are both below league average. In Chicago, they're facing a potent offensive team that allows only 90 percent of the league average goals against. Their power play is just a little below average, which is another good sign for Nashville, but the Blackhawks take few penalties and have a good penalty kill.
Nashville has a lot in common with the 2001-02 Canadiens, who had also missed the playoffs the year before. Just as Nashville's leading scorer is Patric Hornqvist with a scant 51 points, the Habs' leading scorer was Yanic Perreault with only 56.
The key in Montreal was that the Habs had Vezina and Hart Trophy champion Jose Theodore standing on his head between the pipes, so Pekka Rinne will probably have to play out of his mind to shut down Chicago's amazing arsenal of offensive talent.
Los Angeles Kings vs. Vancouver Canucks
Historical chance of an upset: 35 percent
Closest equivalent: The 1992-93 Canadiens, who upset the Quebec Nordiques 4-2 with a weaker power play than Los Angeles.
The Kings are a little bit above average both offensively and defensively, which is a good sign for pulling off the upset. They have a terrific power play, but their penalty killing is just a touch below average. In Vancouver, they're facing a strong offensive team that's almost as good defensively, with a power play certainly potent enough to reduce the chances of an upset.
In the 10 closest historical matches to this series, only twice was there an upset: once by the aforementioned 1992-93 Canadiens, and the next season by the Canucks over the Calgary Flames. The good news for the Kings is that both those teams went on to the Stanley Cup. While it doesn't appear that Los Angeles has a better chance of an upset than anyone else, there's at least some precedent that the Kings could go deep if they do pull it off.
Detroit Red Wings vs. Phoenix Coyotes
Historical chance of an upset: 50 percent
Closest equivalent: The 2003-04 Canadiens, who upset Boston 4-3, which actually had a much better power play than Phoenix.
It feels almost crazy to include the Red Wings as an underdog. The Phoenix franchise hasn't won a playoff series since the Winnipeg Jets beat the Flames in 1986-87. The Coyotes' 19-7 record in 4-on-4 overtimes and shootouts won't help them in the postseason, meaning that they're fundamentally a 31-25-26 team acting as a favorite against a team that was 33-24-25. In the pre-lockout days, that would make Detroit a three-point favorite, not a five-point underdog.
Detroit has a defensive mindset, scoring and allowing a number of goals less than the league average, which has historically improved a team's odds of an upset. The Wings also are above average in special teams and take comparably few penalties. In Phoenix, they're also facing a low-scoring defensive team, but one that takes slightly more penalties than average and has a weak power play, which is another factor which traditionally foreshadows an upset.
Add everything up and you can hardly call it an upset if the defending Western Conference champions win this one.
A version of this story originally appeared on ESPN Insider .
Robert Vollman is an author of Hockey Prospectus.
You can contact Robert by clicking here or click here to see Robert's other articles.