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When Pittsburgh Penguins center Evgeni Malkin hit a snap shot past Detroit Red Wings goalie, Chris Osgood, just under 17 minutes into Game Two of the National Hockey League’s Stanley Cup Finals on Sunday, Pittsburgh fans probably grew optimistic. Their team had scored first, seeming to make a victory much more likely.
That’s the kind of likelihood often cited by sportscasters. After all, if a team scores first, it has an edge, and it might have scored because it’s a better team. But Sunday night, it was not to be: When the final buzzer sounded, the score was Red Wings 3, Penguins 1.
So what were the chances the Penguins would lose?
About 29 percent, according to Jack Brimberg, a professor of operations research at the Royal Military College of Canada in Kingston, Ontario.
In a paper soon to appear in the International Journal of Operational Research, Brimberg and his colleague, Bill Hurley, addressed two questions: Just how important is the first goal in determining a hockey game’s outcome? And, how is that probability affected by the time remaining on the score clock?
The researchers started by assuming that when a hockey puck first hits the ice, both teams have an equal chance of winning the game -- although that could be adjusted for where a team is in the standings or other factors. Those chances change as soon as someone scores that first goal, according to their research.
Brimberg and Hurley, who have also published papers together on football and the triple jump, used a sample of 300 observations from the 2005-2006 NHL regular season to make some estimates. (They didn’t directly study soccer data, but suggest the numbers would be similar.) They found that if a team scored just 5 minutes after the opening face-off -- with 55 minutes more to play in the game -- their chances of winning increase from 50 to 70 percent. This probability continues to rise the further into the game the initial goal was scored: If only 15 minutes remain on the clock, a team will go on to win about 83 percent of the time.
That still leaves the non-scoring team with almost a one in five chance at victory. “We’re talking probability, not certainty,” says Brimberg. He notes many factors that could override his numbers, from “bad luck” to a “bad bounce of the puck.”
What about the Penguins’ loss in Game Two? “A team can outplay another team and still lose,” he says.
Game Three is tonight. As we write this, the Penguins still have a 50 percent shot at winning. Of course, there may be sportscasters that disagree.
Image of Pittsburgh Penguin Sidney Crosby by pointnshoot via Flickr